Electrophotographic light-receiving member having surface region with high ratio of Si bonded to C

ABSTRACT

An electrophotographic light-receiving member comprises a substrate, a photoconductive layer formed on the substrate and composed of a non-single crystal material containing a base component silicon atoms and a surface layer (surface-side region) made of a non-single crystal material containing silicon, carbon and hydrogen atoms, in which the ratio of silicon atoms having at least one bond to a carbon atom in the surface layer is at least 50% of the total number of silicon atoms. The electrophotographic light-receiving member has good initial electrophotographic properties and particularly good durability under a high-humidity environment.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electrophotographic light-receivingmember having sensitivity to electromagnetic waves such as light(including ultraviolet rays, visible rays, infrared rays, X-rays, γ-raysand the like).

2. Description of the Related Art

In the field of image formation, photoconductive materials used forforming a light-receiving layer in an electrophotographiclight-receiving member are required to have properties such as highsensitivity, high SN ratio, absorption spectral properties which conformwith the spectral properties of the electromagnetic wave appliedthereto, high photoresponsiveness, desired dark resistance values,harmlessness to human bodies during use and the like.

A photoconductive material found to have such excellent properties isamorphous silicon (referred to as "A-Si" hereinafter). For example,Germany Patent Laid-Open Nos. 2746967 and 2855718 disclose theapplication of A-Si to an electrophotographic light-receiving member.

Japanese Patent Laid-Open No. 57-11556 discloses a technique in which asurface barrier layer made of a non-photoconductive amorphous materialcontaining silicon and carbon atoms is provided on a photoconductivelayer made of a silicon-based amorphous material for the purpose ofattempting to improve the electrical, optical and photoconductiveproperties, such as the dark resistance value, photosensitivity,photoresponsibility and the like, of a photoconductive member having aphotoconductive layer comprising an A-Si deposited film, the workingenvironmental properties thereof such as humidity resistance and thelike, and the time stability.

In addition, Patent Application No. 62-168161 discloses a techniquewhich uses as a material for a surface layer a material consisting of anamorphous substance containing as components silicon atoms, carbon atomsand 41 to 70 atomic% of hydrogen atoms.

Further, Patent Application No. 60-67951 discloses a technique for aphotosensitive material in which a light-transmitting insulatingovercoat layer containing amorphous silicon, carbon, oxygen and fluorineis laminated on the photosensitive material.

The above techniques permit improvement in the electrical, optical andphotoconductive properties of an electrophotographic light-receivingmember, the working environmental properties and durability thereof, andthe quality of the image formed.

On the other hand, as the copying speed, the printing speed (imageforming speed) and durability of an electrophotographic apparatus arerapidly increased, the frequency of maintenance must be decreased fordecreasing the service cost by improving the reliability of each of theparts of the apparatus. In these circumstances, an electrophotographiclight-receiving member can be continuously repeatedly used under variousenvironmental conditions for a longer time, without being subjected tomaintenance by a service man.

In this situation, the fact is that conventional electrophotographiclight-receiving members have room for improvement.

Particularly, the repeated use of the members at a high speed for a longtime under high humidity sometimes causes the phenomenon that the finelines on the image formed are blurred (image flowing), and in theextreme case, the characters of the image cannot be read. In addition,once an electrophotographic light-receiving member in anelectrophotographic apparatus produces the above phenomenon, it willcontinue to produce image blurring even if it is returned toenvironmental conditions under relatively low humidity which previouslyproduced no image blurring. In a conventional method of preventing suchimage blurring caused under high humidity, a drum is heated fordecreasing the relative humidity on the surface of the drum. However,this method requires heating of the surface of the drum to an extremelyhigh temperature. Thus, the cost of the apparatus and the electricityconsumption are increased, and the toner used sometimes adheres to thesurface of the drum depending upon the set temperature.

In addition, when a light-receiving member having a hard surface withhigh durability is repeatedly used for a long time, as described above,the toner used sometimes adheres to the drum (filming), producingnonuniformity in density and blurs on the image formed.

SUMMARY OF THE INVENTION

It is an object of the present invention to solve the above-describedproblems of a conventional electrophotographic light-receiving memberhaving a light-receiving layer made of A-Si.

Namely, it is a main object of the present invention to provide anelectrophotographic light-receiving member having a light-receivinglayer made of a silicon-based non-single crystal material which haselectrical, optical and photoconductive properties which aresubstantially constantly stable without depending upon the workingenvironment, which has excellent optical fatigue resistance, excellentdurability without any deterioration during repeated use, and excellentmoisture resistance, and which shows substantially no residualpotential.

According to a first aspect of the present invention, anelectrophotographic light-receiving member comprises a substrate and alight-receiving layer formed on the substrate. The light-receiving layerhas a surface layer or a surface-side region formed of a non-singlecrystal material comprising silicon, carbon and hydrogen atoms, whereinthe ratio of silicon atoms each having at least one bond to a carbonatom in the surface layer or surface-side region is at least 50% of thetotal number of silicon atoms in the surface layer or surface-sideregion.

According to another aspect of the present invention, anelectrophotographic light-receiving member comprises a non-singlecrystal layer comprising at least silicon, carbon, oxygen and hydrogenatoms on an outermost surface layer, wherein the ratio of silicon atomscombined with carbon atoms in the non-single crystal layer is 50 to 100atomic % of the total number of silicon atoms therein, the ratio ofsilicon atoms combined with oxygen atoms in the non-single crystal layeris 10 to 30 atomic % of the total number of silicon atoms therein, andthe non-single crystal layer is substantially composed of a non-singlecrystal (Si_(x) C_(y) O_(z))_(t) H_(u), wherein 0.1≦x≦0.4, 0.4≦y≦0.7,0.05 ≦z≦0.2, x+y+z=1, 0.3≦t≦0.59, 0.41 ≦u≦ 0.7, and t+u=1.

According to yet another aspect of the present invention, anelectrophotographic light-receiving member comprises a non-singlecrystal layer containing at least silicon, carbon, oxygen and hydrogenatoms on an outermost surface, wherein the ratio of silicon atomscombined with carbon atoms in the non-single crystal layer is 50 to 100atomic % of the total number of silicon atoms, the ratio of siliconatoms combined with oxygen atoms is 10 to 30 atomic % of the totalnumber of silicon atoms, the ratio of carbon atoms combined with oxygenatoms is 10 to 30 atomic % of the total number of carbon atoms, and thenon-single crystal layer is substantially composed of a non-singlecrystal silicon having the formula (Si_(x) C_(y) O_(z))_(t) H_(u),wherein 0.1≦x≦0.4, 0.4≦y≦0.7, 0.05≦z≦0.2, x+y+z=1, 0.3≦t≦ 0.59,0.41≦u≦0.7, and t+u=1.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of a layer structure for explaining thelayer structure of an electrophotographic light-receiving memberaccording to the present invention;

FIGS. 2(A), (B) and (C) are explanatory views respectively showingexamples of the uneven shape of the surface of a substrate;

FIG. 3 is an explanatory view showing another example of the unevenshape of the surface of a substrate;

FIG. 4 is a schematic drawing showing a method of forming the example ofthe uneven shape shown in FIG. 3;

FIG. 5 is an explanatory view showing a further example of the unevenshape of a substrate;

FIG. 6 is a schematic drawing showing an example of apparatuses forproducing a drum by microwave discharge for forming a light-receivinglayer of an electrophotographic light-receiving member according to thepresent invention;

FIG. 7 is a plan view of the production apparatus shown in FIG. 6; and

FIGS. 8 and 9 are drawings showing an example of spectra obtained byESCA (Electron Spectroscopy for Chemical Analysis) of the surface of anelectrophotographic light-receiving member according to the presentinvention.

DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION

In an electrophotographic light-receiving member according to thepresent invention which enables the above-described problems to besolved and the objects to be achieved, a ratio of bonds between siliconand carbon atoms in the region on the external surface side or thesurface layer of the electrophotographic light-receiving member is setto a value within a desired region.

Particularly, the ratio of silicon atoms each having at least one bondto a carbon atom to the total number of silicon atoms in the surfacelayer or the surface region is set to be at least 50 atomic %.

It is also desirable to more sufficiently solve the above-describedfilming problem to respectively set the ratio of bonds between siliconand carbon atoms and the ratio of bonds between silicon and oxygen atomsto values within desired ranges.

Particularly, the ratio of silicon atoms each having at least one bondto a carbon atom to the total number of silicon atoms in the surfacelayer or surface region is at least 50 atomic %, and the ratio ofsilicon atoms each having at least one bond to an oxygen atom to thetotal number of silicon atoms therein is within the range of 10 to 30atomic %.

The electrophotographic light-receiving member of the present inventioncomprises a substrate and a light-receiving layer having aphotoconductive layer region which is made of a silicon-based non-singlecrystal material containing as a component at least one of hydrogen andhalogen atoms and which exhibits photoconductivity, and a surface layerregion which is made of a non-single crystal material containing ascomponents silicon, carbon and hydrogen atoms, both regions being formedon the substrate, wherein the ratio of silicon atoms each having atleast one bond to a carbon atom in the surface layer region is at least50% of the total number of silicon atoms in the surface layer region.

In another feature of the invention, the electrophotographiclight-receiving member has an outermost surface comprising a non-singlecrystal layer which contains at least silicon, carbon, oxygen andhydrogen atoms, wherein the ratio of silicon atoms combined with carbonatoms in the non-single crystal layer is 50 to 100 atomic % of the totalnumber of silicon atoms, the ratio of silicon atoms combined with oxygenatoms is 10 to 30 atomic % of the total number of silicon atoms, and thenon-single crystal layer is made of a non-single crystal (Si_(x) C_(y)O_(z))_(t) H_(u) (wherein 0.1≦x≦ 0.4, 0.4≦y≦0.7, 0.05≦z0.2, x+y+z=1,0.3≦ t≦0.59, 0.41≦u≦0.7, t+u=1).

In a further feature of the invention, the electrophotographiclight-receiving member has an outermost surface comprising a non-singlecrystal layer which contains at least silicon, carbon, oxygen andhydrogen atoms, wherein the ratio of silicon atoms combined with carbonatoms in the non-single crystal layer is 50 to 100 atomic % of the totalnumber of silicon atoms, the ratio of silicon atoms combined with oxygenatoms is 10 to 30 atomic % of the total number of silicon atoms, theratio of carbon atoms combined with oxygen atoms is 10 to 30 atomic % ofthe total number of carbon atoms, and the non-single crystal layer ismade of non-single crystal silicon expressed by the formula (Si_(x)C_(y) O_(z))_(t) H_(u) (wherein 0.1≦x≦0.4, 0.4≦y≦0.7, 0.05 ≦z≦0.2,x+y+z=1).

The electrophotographic light-receiving member of the present inventiondesigned so as to have the above layer structure is capable of solvingall the above-mentioned problems and shows extremely excellentelectrical, optical and photoconductive properties, durability andworking environmental properties.

The present invention can provide an electrophotographic light-receivingmember showing an excellent property for preventing the occurrence offilming.

EXAMPLE

The electrophotographic light-receiving member of the present inventionis described below.

As a result of energetic investigations conducted by the inventors withattention directed to the point that the above problems can be solved byimproving the surface layer, the inventors found that the object isachieved by specifying a method of bonding silicon atoms in the surfacelayer.

The inventors believe that an electrophotographic apparatus whichemploys a conventional electrophotographic light-receiving memberproduces image blurring under a high-humidity environment due to the twofollowing phenomena which are considered as important mechanisms forimage blurring:

(1) The phenomenon that hygroscopic substances such as oxides likeNO_(x) are generated during corona discharge by a charger, causing paperpowder produced from transfer paper and the like to adhere to thesurface of the light-receiving member and absorb water at high humidity.The resistance is therefore decreased, and image flowing thus occurs.

(2) The phenomenon that the reaction of the material of the surface ofthe light-receiving member with oxygen contained in water and air due tocorona energy causes a decrease in resistance, or an oxide which isdecreased in resistance by absorption of water is produced, therebycausing image blurring.

Most of the substances adhered due to the phenomenon (1) can be removedby rubbing the light-receiving member with a toner, an abrasivecontained in the toner, a blade or the like during theelectrophotographic process. If the adhered substances cannot besufficiently removed, the light-receiving member is separated from theelectrophotographic apparatus by a service man so that the substance canbe completely or substantially completely removed (to an extent whichhas no or substantially no effect on the formation of an image) bywiping the surface of the member with water, an organic solvent or thelike.

It is also effective as a measure against the image blurring caused bythe phenomenon (1) to decrease the relative humidity of the surface byheating the light-receiving member.

However, the image blurring caused by the mechanism described in thephenomenon (2) can hardly be removed by rubbing the light-receivingmember with a toner, an abrasive contained in the toner, a blade or thelike, or wiping the surface the light-receiving member with water, anorganic solvent or the like by a service man.

The method of decreasing the relative humidity of the surface of thelight-receiving member by heating it is only slightly effective as ameasure against the image blurring caused by the phenomenon (2). If thelight-receiving member is heated to a high temperature, the method hasan effect.

In addition, the phenomenon (2) frequently causes problems other thanthe image blurring, e.g., a decrease in sensitivity, an increase inresidual potential and the like.

Previously, although the above two phenomena are not clearly separatelyconsidered, since, in fact, the image flowing is mostly caused by thephenomenon (1), no critical problem occurs in the market.

However, since the development of an electrophotographic apparatusprovided with no means for heating a light-receiving member for thepurposes of cost cutting, energy saving and the like, and since copyingis continuously repeated at a higher speed for a longer time than withconventional apparatus, attention is paid to image blurring which isinsufficiently prevented by the conventional measures and which iscaused by the phenomenon (2).

As described above, a surface layer or a surface region (genericallynamed "surface layer" hereinafter) of a light-receiving member isgenerally made of a non-single crystal material containing as componentssilicon, carbon and hydrogen atoms for the purpose of improving theelectrical, optical and photoconductive properties, workingenvironmental properties, durability and the quality of the imageformed.

The amount of carbon atoms contained in such a surface layer is 1×10⁻³to 90 atomic %, preferably 10 to 80 atomic %, relative to 100% of thetotal of silicon and carbon atoms. When the surface layer is formedirrespective of the state of bonding between silicon atoms and carbonatoms, the silicon and carbon atoms are not uniformly distributed,thereby producing a state wherein portions with a high content ofsilicon atoms and portions with a high content of carbon atoms aremixed.

The number of silicon atoms each having at least one bond to a carbonatom is thus smaller than the value estimated from the abovecomposition.

On the other hand, the inventors found that phenomenon (2) is generatedunder corona discharge by bonding of oxygen with the dangling bonds ofthe silicon atoms which are present in the surface layer initially orwhich are produced by breakage of Si-H and Si-Si bonds, caused by coronaenergy. As a result of ESCA analysis of the surface of a light-receivingmember which is produced irrespective of the bonding between silicon andcarbon atoms and which produces the phenomenon (2), it was confirmedthat about 10 to 30% of silicon atoms are joined to oxygen atoms. If thestate of bonding between silicon and oxygen atoms is expressed bySiO_(z), z is 1.0 to 1.5.

However, results Of many experiments showed that if a silicon atom hasat least one bond to a carbon atom, the above-described oxidation is noteasily produced. In this case, even if the oxidation is produced, theeffect on the electrophotographic properties is decreased. When alight-receiving member is produced with sufficient consideration givento the ratio of bonding between silicon and carbon atoms, image blurringand the like are effectively removed.

It is only slightly effective to simply increase the flow rate of gascontaining carbon atoms in the raw material gases for the purpose ofincreasing the probability of bonding between silicon and carbon atoms.As described above, this is because silicon and carbon atoms are notuniformly distributed in a deposited film. It is therefore difficult toincrease the ratio of silicon atoms each having at least one bond to acarbon atom to 30% or more of the total silicon atoms contained in thesurface layer by simply increasing the flow rate of the gas containingcarbon atoms. In addition, when the amount of carbon atoms is increased,other properties such as the mechanical strength required for anelectrophotographic light-receiving member, the sufficiently wideoptical band gap and the like are sometimes deteriorated, withinsufficient removal of the image blurring.

In the present invention, the surface layer is formed by using amaterial in which the ratio of silicon atoms each having at least onebond to a carbon atom to the total number of silicon atoms is set to avalue which is higher than conventional values, so that the aboveproperties which are opposite to each other can be satisfactorilyimproved.

Further, in the present invention, the surface layer is formed by usinga material in which the ratio of silicon atoms each having at least onebond to a carbon atom and the ratio of silicon atoms each having atleast one bond to an oxygen atom relative to the total number of siliconatoms, are respectively specified to values which are higher thanconventional values so that the weathering resistance and environmentalproperties can be improved without the mechanical strength andtransparency (transmitting an electromagnetic wave having a desiredwavelength) deteriorating, and an electrophotographic light-receivingmember having a great effect of preventing toner filming can beachieved.

Although the detailed function of the effect of preventing toner filmingis not clear, it is believed that when the bonding among the silicon,carbon and oxygen atoms is optimum, the formation of weak bondingbetween the resin in the toner and the surface of the light-receivingmember, which causes the occurrence of filming, can be minimized.

A photoconductive member of the present invention is described in detailbelow with reference to the drawings.

FIG. 1 is a schematic drawing of the layer structure of anelectrophotographic light-receiving member in accordance with apreferred embodiment of the present invention.

The electrophotographic light-receiving member 100 shown in FIG. 1 has asubstrate 101 used for a light-receiving member and a light-receivinglayer 102 provided on the substrate 101. The light-receiving layer 102has a photoconductive layer 103 which is made of A-Si(H, X) (asilicon-based non-single crystal material containing hydrogen and/orhalogen atoms) and which has photoconductivity, and a surface layer 104which is made of a non-single crystal material containing silicon andcarbon atoms. In the surface layer 104, at least a surface-side regionthereof contains a ratio of at least 50% silicon atoms each having atleast one bond to a carbon atom relative to the total number of siliconatoms in the surface layer.

The substrate used in the present invention may either beelectroconductive or insulative. Examples of electroconductivesubstrates include metals such as NiCr, stainless steel, Al, Cr, Mo, Au,In, Nb, Ta, V, Ti, Pt, Pb, Fe and the like; alloys and laminates thereofand the like.

Examples of insulating substrates that are generally used include filmsand sheets of synthetic resins such as polyester, polyethylene,polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride,polyvinylidene chloride, polystyrene, polyamides and the like; glass;ceramics, paper. Any one of these insulating substrates preferably hasat least one surface which is subjected to electroconductive treatment.It is desirable to provide the light-receiving layer on the thus-treatedsurface.

In the case of glass, for instance, a thin film is formed on a surfaceof the glass by using at least one material selected from the groupconsisting of NiCr, Al, Cr, Mo, Au, Ir, Nb, Ta, V, Ti, Pt, Pd, In₂ O₃,SnO₂, ITO (In₂ O₃ +SnO₂) and the like so that electroconductivity isprovided to the surface. In the case of a synthetic resin film such as apolyester film or the like, a thin film is formed on a surface of thefilm by vacuum deposition, electron beam deposition, sputtering or thelike of at least one metal selected from the group NiCr, Al, Ag, Pb, Zn,Ni, Au, Cr, Mo, Ir, Nb, Ta, V, Ti, Pt and the like or laminating thesurface with at least one of the metals so that electroconductivity isprovided to the surface. The substrate can be formed into a desiredshape such as a cylindrical, belt-like, plate-like shape or the like,which can be determined according to desire. For example, an endlessbelt-like or cylindrical shape is preferable for continuous high-speedcopying. The thickness of the substrate is appropriately determined sothat a desired electrophotographic light-receiving member can be formed.When the electrophotographic light-receiving member is required to haveflexibility, the substrate is made as thin as possible within a rangewhich allows the function as a substrate to be sufficiently exhibited.However, in this case, the substrate is generally 10 μ or more in viewof the production and handling of the substrate or the mechanicalstrength thereof.

In addition, when an image is recorded by using coherent light such aslaser beams, desired irregularities may be provided on a surface of thesubstrate for the purpose of removing defective images caused by aso-called inference fringe pattern, which is produced in a visibleimage.

FIGS. 2(A) to 2(C) are schematic sectional views of substrates whichrespectively show examples of irregularities.

When irregularities are provided on a surface of the substrate, acutting tool having a V-shaped cutting edge is fixed to a predeterminedposition of a cutting machine such as a milling machine, a lathe or thelike. For example, a cylindrical substrate is regularly moved in apredetermined direction while being rotated according to a program sothat the surface of the substrate can be accurately cut to formirregularities with a desired shape, pitch and depth. The reverse V-formlinear projecting portion of the irregularities formed by the abovecutting method has a helical structure along the axis of the cylindricalsubstrate. The helical structure of the reverse V-form linear projectingportion may be a double or treble helical structure or a cross-helicalstructure.

Further, a delay line structure along the axis may be added to thehelical structure.

The cross-sectional form of the convex portion of the irregularitiesprovided on the surface of the substrate preferably is a reverse V-formso as to ensure that there are controlled unevenness of thickness in aminute column for each of the layers formed, and good adhesion anddesired electrical contact properties between the substrate and thelayer provided directly thereon. However, as shown in FIG. 2, thesectional form of the convex portion is preferably substantially anequilateral triangle, a right-angled triangle or an unequilateraltriangle. Of these forms, an equilateral triangle and right-angledtriangle are most preferable.

In the present invention, the dimensions of the irregularities providedon the surface of the substrate in a controlled state are determined inconsideration of the points below so that the object of the presentinvention can be consequently achieved.

That is, firstly, the amorphous silicon (A--Si(H, X)) which containshydrogen and/or halogen atoms and which forms the light-receiving layeris sensitive to the state of the surface on which the layer is formed,and the layer quality significantly depends upon the surface state.

It is therefore necessary to determine the dimensions of theirregularity provided on the surface of the substrate so that thequality of the A--Si (H, X) layer does not deteriorate.

Secondly, if the free surface 105 of the light-receiving layer hasextreme irregularities, the image formed cannot be completely cleanedduring the cleaning process after the formation thereof.

There is also the problem that in the case of cleaning with a blade, theblade is easily damaged.

As a result of investigation of the problems with respect to theformation of a layer, the problems with respect to theelectrophotographic process and conditions for preventing the occurrenceof an interference fringe pattern, the pitch of the concave portions onthe surface of the substrate is preferably 500 to 0.3 μm, morepreferably 200 to 1 μm, most preferably 50 to 5 μm.

The maximum depth of the concave portions is preferably 0.1 to 5 μm,more preferably 0.3 to 3 μm, most preferably 0.6 to 2 μm. When the pitchand the maximum depth of the concave portions are within the aboveranges, the inclination of the slope of each concave portion (or linearprojecting portion) is preferably 1° to 20°, more preferably 3° to 15°,most preferably 4° to 10°.

The maximum difference in thickness based on nonuniformity in the layerthickness of each of the layers deposited on the substrate is preferably0.1 to 2 μm, more preferably 0.1 to 1.5 μm, most preferably 0.2 to 1 μm,within the same pitch.

In another method of removing defective images caused by an interferencefringe pattern when coherent light such as laser beams or the like isused, irregularities are provided by forming a plurality of finespherical dimples on the surface of the substrate.

Namely, the size of the irregularities which are composed of a pluralityof fine spherical dimples and which are formed on the surface of thesubstrate is smaller than the resolving power required for theelectrophotographic light-receiving member.

Although the shape of the surface of the substrate and a preferableexample of methods of producing the substrate in the electrophotographiclight-receiving member of the present invention are described withreference to FIG. 4, the shape and production method for the substratein the light-receiving member of the invention are not limited to them.

FIG. 4 is a schematic drawing of a typical example of the shape of thesubstrate surface in the electrophotographic light-receiving memberaccording to the present invention in which an irregular portion isenlarged.

In FIG. 4, reference numeral 1601 denotes a substrate; reference numeral1602, a surface of the substrate; reference numeral 1603, a rigidsphere; and reference numeral 1604, a spherical dimple.

FIG. 4 also shows a preferred example of methods of obtaining thesurface shape of the substrate. Namely, FIG. 4 shows that the sphericalrecess 1604 can be formed by causing the rigid sphere 1603 togravitationally fall from a position at a predetermined height from thesubstrate surface 1602 so that the sphere 1603 collides against thesurface 1602 of the substrate. A plurality of spherical dimples 1604having substantially the same radius of curvature R and the same width Dcan be formed on the surface 1602 of the substrate by causing aplurality of rigid spheres 1603 having substantially the same radius R'to simultaneously or successively fall from substantially the sameheight h.

FIG. 5 shows a typical example of the substrates formed withirregularities comprising a plurality of spherical dimples formed on thesurface thereof as described above.

The radius of curvature R and width D of each of the spherical dimpleswhich form the irregular form of the surface of the substrate of theelectrophotographic light-receiving member of the invention areimportant factors for efficiently achieving the effect of preventing theoccurrence of an interference fringe pattern which is confirmed in theimage printed by the light-receiving member according to the presentinvention. As a result of experiments performed by the inventors, theinventors found the following facts:

When the radius R of curvature and width D satisfy the followingequation: ##EQU1## at least 0.5 Newton ring is produced in each of thedimples by the shearing interference.

When R and D satisfy the following equation: ##EQU2## at least oneNewton ring is produced in each of the dimples by the shearinginterference.

This finding shows that the D/R value is at least 0.035, preferably atleast 0.055, for dispersing the interference fringes produced in thewhole light-receiving member in each of the dimples, thereby preventingthe occurrence of interference fringes confirmed in the image printed byusing the light-receiving member.

The width D of each of the dimples which form irregularities is at mostabout 500 μm, preferably 200 μm or less, more preferably 100 μm or less.

In the present invention, the photoconductive layer 103 which is formedon the substrate 101 and which partially forms the light-receiving layer102 has the semiconductor properties below and is made of A--Si (H, X)showing photoconductivity for the light applied thereto.

(1) p-type A--Si(H,X)--containing an acceptor only or both the acceptorand a donor in which the relative content of the acceptor is higher.

(2) p⁻ -type A--Si(H,X)--in Type (1), the content (Na) of the acceptoris lower, or the relative content of the acceptors is lower.

(3) n-type A--Si(H,X)--containing a donor only or both the donor and anacceptor in which the relative content of the donor is higher.

(4) n⁻ -type A--Si(H,X)--in Type (3), the content (Nd) of the donor islower, or the relative content of the acceptor is lower.

(5) i-type A--Si(H,X)--Na≃Nd≃0 or Na≃Nd

In the present invention, F, Cl, Br and I are preferable as a halogenatom (X) contained in the photoconductive layer 103, and F and Cl areparticularly preferable.

In the present invention, the photoconductive layer 103 made ofA--Si(H,X) is formed by a vacuum deposition method which employs adischarge phenomenon, for example, a glow discharge process, a microwavedischarge process, a sputtering process, an ion plating process or thelike. For example, when an amorphous layer made of A--Si(H,X) is formedby the glow discharge process, Si supplying raw material gas which cansupply silicon atoms (Si) and raw material gas for supplying hydrogenatoms (H) and/or halogen atoms (X) are introduced into a depositionchamber in which the pressure can be reduced, and glow discharge isinduced in the deposition chamber so that the layer of A--Si(H,X) isformed on a predetermined surface of a substrate placed at apredetermined position. When such a layer is formed by the sputteringprocess, gas for supplying hydrogen atoms (H) and/or halogen atoms (X)may be introduced into a sputtering deposition chamber during sputteringof a Si target in an atmosphere of inert gas such as Ar, He or the likeor a gas mixture based on the inert gases.

Examples of gases that are effectively used as raw material gases forsupplying Si in the present invention include silicon hydrides (silanes)such as SiH₄, Si₂ H₆, Si₃ H₈, Si₄ H₁₀ and the like, all of which aregaseous or can be gasified. SiH₄ and Si₂ H₆ are particularly preferablefrom the viewpoints of ease of handling in the work of forming a layer,high efficiency of Si supply and the like.

Preferable examples of raw material gases effectively used for supplyinghalogen atoms in the present invention include many halogen compoundssuch as halogen gas, halides, interhalogen compounds,halogen-substituted silane derivatives and the like, all of which aregaseous or can be gasified.

Silicon compounds which consist of silicon and halogen atoms, which aregaseous or can be gasified and which contain halogen atoms can also beexemplified as effective compounds in the present invention.

Typical examples of halogen compounds that can be preferably used in thepresent invention include halogen gases such as fluorine, chlorine,bromine, iodine and the like, and interhalogen compounds such as BrF,ClF, ClF₃, BrF₅, BrF₃, IF₃, IF₇, ICI, IBr and the like.

Typical examples of silicon compounds containing halogen atoms, i.e.,halogen-substituted silane derivatives, include silicon halides such asSiF₄, Si₂ F₆, SiCl₄, SiBr₄ and the like.

When the photoconductive member which is characteristic of the presentinvention is formed by the glow discharge process using such a siliconcompound containing halogen atoms, silicon halide gas used as rawmaterial gas for supplying Si and gases such as Ar, H₂, He or the likeare introduced, at a predetermined mixing ratio and flow rates, into thedeposition chamber for forming the photoconductive layer, and a plasmaatmosphere is formed by inducing glow discharge so that thephotoconductive layer can be formed on a predetermined substrate. Inthis embodiment, a predetermined amount of silicon compound gascontaining hydrogen atoms may be further mixed with the above gasmixture for the purpose of supplying hydrogen atoms.

The above gases may be used singly or in a mixture of a plurality ofgases with a predetermined mixing ratio.

A layer of A--Si(H,X) can be formed by the reaction sputtering or ionplating process. In the sputtering process, a Si target is sputtered ina predetermined gas plasma atmosphere. In the ion plating process, apolycrystal silicon or single crystal silicon received as an evaporationsource in an evaporation chamber is heated and evaporated by aresistance heating method or an electron beam (EB) method, and theevaporated substance is passed through a predetermined gas plasmaatmosphere.

When halogen atoms are introduced into the layer formed by thesputtering process or the ion plating process, gas of the halogencompound or silicon compound containing halogen atoms may be introducedinto the deposition chamber to form a plasma atmosphere of the gas.

When hydrogen atoms are introduced into the layer, raw material gas forsupplying hydrogen atoms, e.g., H₂ or the above silanes, may beintroduced into the sputtering deposition chamber to form a plasmaatmosphere of the gas.

In the present invention, although any one of the halogen compounds andhalogen-containing silicon compounds is effectively used as raw materialgas for supplying halogen atoms, other examples of compounds that can beeffectively used as a starting material for forming the photoconductivelayer include hydrogen halides such as HF, HCl, HBr, HI and the like,halogen-substituted silicon hydrides such as SiH₂ F₂, SiH₂ I₂, SiH₂ Cl₂,SiHCl₃, SiH₂ Br₂, SiHBr₃ and the like, all of which are gaseous or canbe gasified and which contain hydrogen atoms as a component.

In the present invention, such halogen compounds containing hydrogenatoms are preferably used as raw materials for supplying halogen atomsbecause hydrogen atoms which are extremely effective for controllingelectrical or photoelectric properties are introduced into the layer atthe same time the introduction of halogen atoms during the formation ofthe layer.

Halogen atoms can also be structurally introduced into the layer bycausing gas of H₂ or a silicon halide such as SiH₄, Si₂ H₆, Si₂ H₈, Si₄H₁₀ or the like to coexist with a silicon compound for supplying Si inthe deposition chamber and inducing discharge therein.

For example, in the reaction sputtering process, gas for supplyinghalogen atoms, H₂ gas and, if required, inert gas such as He, Ar or thelike, are introduced into the deposition chamber, and a plasmaatmosphere is formed therein so that a layer of A--Si(H,X) can be formedon a substrate by sputtering the Si target used.

B₂ H₆ gas or the like may be further introduced for doping the layerwith impurities.

The amount of hydrogen atoms (H), the amount of halogen atoms (X) or thetotal of hydrogen and halogen atoms, which are contained in thephotoconductive layer of the electrophotographic light-receiving memberformed in the present invention is preferably 1 to 40 atomic %, morepreferably 5 to 30 atomic %.

The amount of hydrogen atoms (H) and/or halogen atoms (X) contained inthe layer may be controlled by, for example, controlling the temperatureof the substrate used and/or the amount of the starting materialintroduced into the deposition apparatus for introducing hydrogen atoms(H) or halogen atoms (X) in the layer, discharge power or the like.

Preferable examples of dilution gases which are used for forming thephotoconductive layer by the glow discharge or sputtering process in thepresent invention include rare gases such as He, Ne, Ar and the like.

A desired property of the above semiconductor properties 1 to 5 can beimparted to the photoconductive layer 103 by doping the layer formedwith n-type impurities, p-type impurities or both types of impuritieswhile controlling the amount of impurities during the formation of thelayer. Preferable examples of p-type impurities include atoms such as B,Al, Ga, In, Tl and the like which belong to the Group III in thePeriodic Table. Preferable examples of n-type impurities include atomssuch as N, P, As, Sb, Bi and the like which belong to the Group V in thePeriodic Table. B, Ga, P and Sb are particularly preferable.

In the present invention, the amount of impurities which are doped inthe photoconductive layer 103 for the purpose of obtaining a desiredconduction type is appropriately determined according to desiredelectrical and optical properties. In the case of impurities in theGroup III in the Periodic Table, the amount of the impurities doped maybe 3×10⁻³ atomic % or less. In the case of impurities in the Group V inthe Periodic Table, the amount of the impurities doped may be 5×10⁻³atomic % or less.

The photoconductive layer 103 may be doped with impurities byintroducing a raw material for introducing impurities into thedeposition chamber together with the main raw material used for formingthe photoconductive layer 103 during the formation thereof. It isdesirable to use as such raw material for introducing impurities asubstance which is gaseous at room temperature and atmospheric pressureand which can easily be gasified at least under conditions for formingthe layer.

It is also desirable to appropriately combine A--Si(H,X) of the typesselected from the types (1) to (5) of the A--Si(H,X) layer in view ofcharge polarity or the like, as occasion demands.

Typical examples of starting materials used for introducing impuritiesinclude PH₃, P₂ H₄, PF₃, PF₅, PCl₃, AsH₃, AsF₃, AsF₅, AsCl₃, SbH₃, SbF₃,SbF₅, BiH₃, BF₃, BCl₃, BBr₃, B₂ H₆, B₄ H₁₀, B₅ H₉, B₅ H₁₁, B₆ H₁₀, B₅H₁₂, B₄ H₁₄, AlCl₃, GaCl₃, InCl₃, TlCl₃ and the like.

For example, when the photoconductive layer is formed by the glowdischarge process, in order to contain atoms of at least one kind ofcarbon, oxygen and nitrogen atoms in the photoconductive layer, acompound containing at least one kind of carbon, oxygen and nitrogenatoms may be introduced, together with the raw material gas for formingthe photoconductive layer, into the deposition chamber which allows thepressure to be decreased, and glow discharge may be induced in thedeposition chamber so that the photoconductive layer can be formed.

Examples of carbon-containing compounds that can be used as a rawmaterial for introducing carbon atoms include saturated hydrocarbonshaving 1 to 4 carbon atoms, hydrocarbons of ethylene series having 2 to4 carbon atoms, hydrocarbons of acetylene series having 2 to 3 carbonatoms and the like.

Typical examples of such saturated hydrocarbons include methane (CH₄),ethane (C₂ H₆), propane (C₃ H₈), n-butane (n-C₄ H₁₀), pentane (C₅ H₁₂)and the like. Typical examples of hydrocarbons of ethylene seriesinclude ethylene (C₂ H₄), propylene (C₃ H₆), butene-1 (C₄ H₈), butene-2(C₄ H₈), isobutylene (C₄ H₈), pentene (C₅ H₁₀) and the like. Typicalexamples of hydrocarbons of acetylene series include acetylene (C₂ H₂),methylacetylene (C₃ H₄), butyne (C₄ H₆) and the like.

Alkyl silicides such as Si(CH₃)₄, Si(C₂ H₄)₄ and the like can beexemplified as raw material gas consisting of Si, C and H atoms.

Examples of oxygen-containing compounds that can be used as a rawmaterial for introducing oxygen atoms include oxygen (O₂), carbonmonoxide (CO), carbon dioxide (CO₂), nitrogen monoxide, nitrogen dioxideand the like.

Examples of nitrogen-containing compounds that can be used as a rawmaterial for introducing nitrogen atoms include nitrogen (N₂), nitrogenmonoxide, nitrogen dioxide, ammonia and the like.

For example, when the photoconductive layer is formed by the sputteringprocess, sputtering may be performed by using a sputtering target madeof a mixture of (Si+Si₃ N₄), (Si+SiC) or (Si+SiO₂) with a desired mixingratio or using a target comprising a Si wafer and a Si₃ N₄ wafer, a Siwafer and a SiC wafer or a Si wafer and a SiO₂ wafer. Alternatively, thephotoconductive layer may be formed by sputtering Si or a target in thedeposition chamber in which gas of a compound containing carbon,nitrogen or oxygen is introduced together with sputtering gas such as Argas or the like.

Since the amount of carbon, oxygen or nitrogen which is contained in thephotoconductive layer formed in the present invention has a significanteffect on the characteristics of the electrophotographic light-receivingmember produced, the amount must be appropriately determined accordingto demands. However, the amount is preferably 0.0005 to 30 atomic %,more preferably 0.001 to 20 atomic %, most preferably 0.002 to 15 atomic%.

The thickness of the photoconductive layer 103 is appropriatelydetermined according to desire so that the photocarriers generated byirradiation of light having desired spectral properties are efficientlytransported. The thickness is generally 1 to 100 μ, preferably 2 to 50μ.

The surface layer 104 formed on the photoconductive layer 103 has thefree surface 105 which is provided for achieving the objects of thepresent invention with respect to the humidity resistance, continuousrepeated service properties, electrical voltage resistance, workingenvironmental properties and durability.

In addition, in the present invention, since the amorphous materialsrespectively used for forming the photoconductive layer 103 and thesurface layer 104, which form the light-receiving layer 102, have acommon component, i.e., silicon atoms, chemical stability issufficiently ensured at the interface between both layers.

As a matter of course, there is no clear interface between thephotoconductive layer 103 and the surface layer 104. Namely, the contentof carbon atoms in the photoconductive layer 103 may be graduallyincreased from the outer side thereof so that a desired ratio of bondingbetween silicon and carbon atoms is attained at least in the region onthe surface side.

Having no clear interface between the photoconductive layer 103 and thesurface layer 104 is preferable when coherent light such as laser beamsor the like is used as a light source because the refractive index ischanged or reflection is produced at the interface.

The surface layer 104 is made of an amorphous material [A--(Si_(x)C_(1-x))_(y) H_(1-y) wherein 0<x,y<1] which consists of silicon, carbonand hydrogen atoms.

The surface layer 104 made of A--(Si_(x) C_(1-x))_(y) H_(1-y) is formedby the RF discharge process, the microwave discharge process, thesputtering process or the like. In any one of the processes, reactionmust be controlled so that the number of silicon atoms each having atleast one bond to a carbon atom is different from that of a conventionallayer, relative to the total of number of silicon atoms in the surfacelayer.

In the plasma CVD process, an example of the methods of controlling thebonding of silicon atoms is a method of appropriately selecting the typeof raw material gas and employing the ions produced by applying anelectrical field during discharge like the RF discharge process andmicrowave discharge process.

In a method of controlling reaction so that the number of silicon atomseach having at least one bond to a carbon atom in the layer relative tothe total silicon atoms therein is large, silicon-containing gas such asa silane (SiH₄), silicon tetrafluoride (SiF₄) or the like and/orcarbon-containing gas such as methane (CH₄), carbon tetrafluoride (CF₄)or the like and an alkyl silicide such as tetramethylsilane (Si(CH₃)₄),tetraethylsilane (Si(C₂ H₄)₄) or the like are used as raw materialgases. This method is particularly effective for the microwave dischargeprocess.

It is also effective to excite the gas which is used ascarbon-containing gas and which has a double bond or triple bondtogether with the gas containing silicon atoms by employing light, anelectrical field or the like.

In the microwave discharge process, the above method is accompanied byapplication of an electrical field to the discharge space foreffectively bringing ions near the surface of the substrate so that thecontrol effect can be further improved.

Examples of dilution gases used for forming the surface layer 104 in thepresent invention include hydrogen (H₂), argon (Ar), helium (He) and thelike.

In the present invention, it is also effective to introduce anitrogen-containing gas such as nitrogen (N₂), ammonia (NH₃) and thelike, an oxygen-containing gas such as oxygen (O₂), nitrogen monoxide(NO), nitrogen dioxide (NO₂), dinitrogen oxide (N₂ O), carbon monoxide(CO), carbon dioxide (CO₂) and the like, a fluorine compound such asgermanium tetrafluoride (GeF₄), nitrogen fluoride (NF₃) or the like, agas mixture thereof, dopant gases such as diborane (B₂ H₆), boronfluoride (BF₃), phosphine (PH₃) or the like during the formation of thesurface layer 104.

In the present invention, when the amount of alkyl silicide introducedin the film-forming space is preferably 0.12 or more, more preferably0.38 or more, and most preferably 0.90 or more, relative to the total ofthe silicon-containing gas and the carbon-containing gas, the ratio ofbonding between silicon and carbon atoms can be set to a value within adesired range. In some cases, the above-described required propertiesand other required properties were not sufficiently satisfied byintroducing the alkyl silicide only.

The surface layer 104 of the present invention is carefully formed inconsideration of the bonding ratio of silicon and carbon atoms so thatthe required properties are satisfactorily obtained.

Namely, substances consisting of Si, C and H atoms respectively havestructural forms ranging from crystal to amorphous, electrical physicalproperties ranging from conductive to semiconductive and insulative andproperties ranging from photoconductive to non- o photoconductive,depending upon the formation conditions. In the present invention,therefore, the conditions for forming A--Si_(x) C_(1-x) are carefullyselected so that A--Si_(x) C_(1-x) having the desired propertiescorresponding to the desired purpose can be formed.

For example, when the surface layer 104 is provided mainly for thepurpose of improving the voltage resistance, A--(Si_(x) C_(1-x))_(y) :H_(1-y) is formed as an amorphous material showing significantelectrical insulating behavior in the working environment.

When the surface layer 104 is provided mainly for the purpose ofimproving the continuous repetitive working properties and workingenvironmental properties, A--Si_(x) C_(1-x) is formed as an amorphousmaterial having a certain degree of sensitivity to light applied theretoand a degree of electrical insulating properties which is decreased tosome extent.

When the surface layer 104 made of A--(Si_(x) C_(1-x))_(y) : H_(1-y) isformed on the surface of the photoconductive layer 103, the temperatureof the substrate on which a layer is formed is an important factor fordetermining the structure and properties of the layers formed. In thepresent invention, it is thus preferable to carefully control thetemperature of the substrate during formation of a layer so thatA--(Si_(x) C_(1-x))_(y) : H_(1-y) having the intended properties can beformed.

When the surface layer 104 is formed so that the object of the inventionis effectively achieved, a temperature within the optimum range isappropriately selected as the temperature of the substrate according tothe method of forming the surface layer 104. The temperature of thesubstrate is generally 50° to 350° C., preferably 100° to 300° C. Theglow discharge process and sputtering process are advantageous forforming the surface layer 104 because the precise control of thecomponent ratios of the constituent atoms of the layer and the controlof the thickness thereof are relatively easier than the other methods.When the surface layer 104 is formed by these methods, the dischargepower and gas pressure during the formation of the layer are importantfactors which influence the characteristics of A--(Si_(x) C_(1-x))_(y) :H_(1-y) formed, in the same way as the temperature Of the substrate.

The condition of the discharge power for effectively forming, with highproductivity, A--(Si_(x) C_(1-x))_(y) : H_(1-y) having the propertieswhich enable the achievement of the object of the invention is generally10 to 5000 W, preferably 20 to 2000 W, per substrate. In the RFdischarge process, the gas pressure in the deposition chamber isgenerally 0.01 to 2 Torr, preferably 0.1 to 1 Torr. In the microwavedischarge process, the gas pressure is generally 0.2 to 100 mTorr,preferably about 1 to 50 mTorr.

In the present invention, although the desirable ranges of thetemperature of the substrate and the discharge power for forming thesurface layer 104 are described above, these factors for forming thelayer are not separately determined, and the optimum value of each ofthe factors for forming the layer is preferably determined on the basisof the mutual organic connection so that the surface layer 104 ofA--Si_(x) C_(1-x) having desired properties can be formed.

The amounts of the carbon and hydrogen atoms which are contained in thesurface layer 104 in the electrophotographic light-receiving member ofthe present invention are also important factors for forming the surfacelayer 104 having desired properties which enable the achievement of theobject of the invention, like the conditions for formation of thesurface layer 104.

The amount of the carbon atoms contained in the surface layer 104according to the present invention is 40 to 90 atomic %, preferably 55to 85 atomic %, and more preferably 60 to 80 atomic %, of the totalamount of silicon and carbon atoms.

The content of hydrogen atoms is generally 41 to 70 atomic %, preferably41 to 70 atomic %, and more preferably 45 to 60 atomic %, of the totalamount of the constituent atoms. When the hydrogen content is within theabove ranges, the light-receiving member formed is significantlysuperior to conventional members in practical use and thus can besatisfactorily used.

It is generally known that the properties of the electrophotographiclight-receiving member are adversely affected by the defects (mainlydangling bonds of silicon and carbon atoms) present in the surface layermade of A--(Si_(x) C_(1-x))_(y) : H_(1-y). For example, the chargeproperties are deteriorated due to injection of charge from the freesurface or changed due to changes in the surface structure in theworking environment, e.g., under high humidity. The after imagephenomenon occurs during repetitive use due to trapping of charge in thedefects in the surface layer; the charge being injected to the surfacelayer from the photoconductive layer during corona discharge orirradiation of light.

However, the defects in the surface layer are significantly decreased bycontrolling the hydrogen content in the surface layer to be at least 41atomic %. As a result, all the above problems are solved, andparticularly, the electrical properties and high-speed continuoususability can be significantly improved, as compared with conventionallight-receiving members.

On the other hand, if the hydrogen content in the surface layer exceeds71 atomic %, since the hardness of the surface layer is decreased, thelayer cannot sufficiently resist repetitive use. It is thus importantfor obtaining excellent electrophotographic properties to control thehydrogen content in the surface layer so that it is within the aboverange. The hydrogen content in the surface layer can be controlled bycontrolling the flow rate of H₂ gas, the temperature of the substrate,the discharge power, the gas pressure or the like.

If the ratios of the silicon, carbon and hydrogen atoms contained in thelayer are expressed on the basis of A--(Si_(x) C_(1-x))_(y) H_(1-y), itis desirable that x is 0.1 to 0.6, preferably 0.15 to 0.45, and morepreferably 0.2 to 0.4, y is 0.3 to 0.59, preferably 0.35 to 0.59, andmore preferably 0.4 to 0.55.

In the present invention, the bonding state of silicon atoms in thesurface layer other than the above factors is also a very importantfactor. Namely, in the light-receiving member of the present invention,the ratio of silicon atoms each having at least one bond to a carbonatom is at least 50%, preferably at least 60%, and more preferably atleast 70%, of the total number of the silicon atoms in the surfacelayer.

The numerical range of the thickness of the layer according to theinvention is also an important factor for effectively achieving theobject of the invention.

The numerical range of the thickness of the layer in the invention isappropriately determined according to the desired purposes so that theobjects of the invention can be effectively achieved.

In regard to the thickness of the photoconductive layer 103, it is alsonecessary to appropriately determine the thickness of the surface layer104 according to desire on the basis of the organic connectioncorresponding to the properties required for each of the layer regions.In addition, it is preferable to consider economy including productivityand mass productivity.

The thickness of the surface layer 104 in the present invention isgenerally 0.003 to 30 μ, preferably 0.004 to 20 μ, and more preferably0.005 to 10 μ. When no clear interface is present between thephotoconductive layer 103 and the surface layer 104, the thickness ofthe region of A--(Si_(x) C_(1-x))_(y) : H_(1-y) within the above rangemay be considered as the thickness of the surface layer 104 forconvenience's sake.

The thickness of the light-receiving layer of the electrophotographiclight-receiving member 100 in the present invention is appropriatelydetermined so as to meet the desired purpose.

In the present invention, the thickness of the light-receiving layer 102is appropriately determined on the basis of the relation between thethicknesses of the photoconductive layer 102 and the surface layer 103so as to make effective use of each of the properties imparted to thephotoconductive layer 103 and the surface layer 104, both of which formthe light-receiving layer 102, and effectively achieve the object of thepresent invention. The thickness of the light-receiving layer 102 ispreferably determined so that the thickness of the photoconductive layer103 is at least several thousands times the thickness of the surfacelayer 102.

The typical value of the thickness is generally 3 to 100 μ, preferably 5to 70 μ, and more preferably 5 to 50 μ.

In the electrophotographic light-receiving member of the presentinvention, an adhesive layer made of an amorphous material such as Si₃H₄, SiO₂, SiO or the like, which contains at least one of hydrogen andhalogen atoms, at least one of nitrogen and oxygen atoms and a siliconatom, may be provided between the substrate 101 and the photoconductivelayer 103 for the purpose of further improving the adhesiontherebewteen.

It is also preferable to provide a layer or region containing Ge on theside of the substrate for the purpose of effectively absorbing lightwith a long wavelength such as infrared laser beams.

As described above, the surface layer 104 may be made of a non-singlecrystal material [A--(Si_(x) C_(y) O_(z))_(t) H_(u) ] containingsilicon, carbon, oxygen and hydrogen atoms. In this case, an attempt canbe made to improve a measure against filming.

The surface layer 104 made of A--(Si_(x) C_(y) O_(z))_(t) H_(u) can alsobe formed by the RF discharge process, the microwave discharge process,the sputtering process or the like. However, in any one of theprocesses, as described above, the layer is formed by controllingreaction so that the ratios of the number of silicon atoms each havingat least one bond to a carbon atom and the number of silicon atoms eachhaving at least one bond to an oxygen atom relative to the total numberof silicon atoms in the surface layer are different from those inconventional members.

Like the RF discharge process and microwave discharge process, anexample of the methods of controlling the bonding of silicon atoms inthe plasma CVD process is a method of selecting the types of rawmaterial gases and employing the ions produced by applying an electricalfield during discharge.

In a method of controlling the reaction so that the number of siliconatoms each having at least one bond to a carbon atom in the surfacelayer relative to the total silicon atoms therein is greater than aconventional value, it is particularly effective for the microwavedischarge process to use as raw material gases silicon-containing gassuch as silane (SiH₄), silicon tetrafluoride (SiF₄) or the like, and/orcarbon-containing gas such as methane (CH₄), carbon tetrafluoride (CF₄)or the like and an alkyl silicide such as tetramethylsilane (Si(CH₃)₄),tetraethylsilane (Si(C₂ H₄)₄) or the like.

It is also effective to excite the gas used as carbon-containing gas andhaving a double or triple bond, together with silicon-containing gas, byusing light, an electrical field of the like.

In the microwave discharge process, the controlling effect is improvedby applying an electrical field to the discharge space so as toeffectively bring ions near the surface of the substrate in the abovemethod.

Under these conditions, the supply of the raw material gas containingoxygen atoms permits control of the reaction so that the ratio by numberof silicon atoms each having at least one bond to an oxygen atom to thetotal silicon atoms in the surface layer is greater than that obtainedby discharge simply using microwaves. This phenomenon can be moreeffectively performed by changing the material gas used for supplyingoxygen.

As a method of controlling reaction so that the ratio by number ofsilicon atoms each having at least one bond to a carbon atom in thesurface layer to the total silicon atoms therein is small, it iseffective for the microwave discharge process to use saturated bondspecies in which a plurality of silicon atoms or carbon atoms arecombined. For example, disilane (Si₂ H₆), disilicon hexafluoride (Si₂F₆) or the like is used as the raw material gas for silicon atoms, andethane (C₂ H₆), propane (C₃ H₈) or the like is used as the raw materialgas for carbon atoms.

When oxygen atoms are further contained in the layer, it is alsopreferable to determine the amount of the alkyl silicide introducedrelative to the total amount of the silicon-containing gas andcarbon-containing gas which are introduced into the film-forming spaceso as to be within the above-described range. However, if the ratio ofbonding between oxygen and silicon atoms is within a desired range,there is no need for controlling the amount of the alkyl silicideintroduced so that it is within the above range.

As a method of controlling reaction so that the ratio by number ofcarbon atoms each having at least one bond to an oxygen atom in thesurface layer to the total carbon atoms therein is greater thanconventional values, it is effective for the microwave discharge processto use silicon-containing gas such as silane (SiH₄), silicontetrafluoride (SiF₄) or the like, and/or oxygen-containing gas such asoxygen (O₂), water (H₂ O), nitrogen monoxide (NO) or the like and acompound such as carbon monoxide (CO), carbon dioxide (CO₂), ethyl ether(CH₃)₂ O or the like, which contain both carbon and oxygen.

In the present invention, examples of dilution gases that can be usedfor forming the surface layer include hydrogen (H₂), argon (Ar), helium(He) and the like.

It is also effective for the present invention to introduce anitrogen-containing gas such as nitrogen (N₂), ammonia (NH₃) or thelike, a fluorine compound such as germanium tetrafluoride (GeF₄),nitrogen fluoride (NF₃) or the like, a gas mixture thereof or dopantgases such as diborane (B₂ H₆), boron fluoride (BF₃), phosphine (PH₃) orthe like during the formation of the surface layer 104.

The surface layer 104 according to the present invention is carefullyformed in consideration of the ratio of bonds between silicon and carbonatoms and the ratio of bonds between silicon and oxygen atoms or bothratios and the ratio of bonds between carbon and oxygen atoms so thatthe required properties are obtained according to demands.

Namely, substances consisting of Si, C, O and H respectively havestructural forms ranging from crystal to amorphous, electricalproperties ranging from conductive to semiconductive and insulative, andproperties ranging from photoconductive to non-photoconductive,depending upon the conditions for formation thereof. In the presentinvention, therefore, the conditions for formation of A--(Si_(x) C_(y)O_(z))_(t) H_(u) are strictly selected according to desire so that thesubstance having desired properties is formed in correspondence with thedesired purpose.

For example, if the surface layer 104 is provided for the purpose ofimproving the voltage resistance, A--(Si_(x) C_(y) O_(z))_(t) H_(u) isformed as a non-single Crystal material showing significant electricalinsulating behavior in the working environment.

If the surface layer 104 is provided for the purpose of improving thecontinuous repetitive working properties and working environmentalproperties, A--(Si_(x) C_(y) O.sub. z)_(t) H_(u) is formed as anon-single crystal material having a degree of electrical insulatingproperties which is decreased to some extent and a certain degree ofsensitivity to the light applied thereto.

When the surface layer 104 made of A--(Si_(x) C_(y) O_(z))_(t) H_(u) isformed on the surface of the photoconductive layer 103, the temperatureof the substrate during the formation of the layer is an importantfactor which influences the structure and properties of the layerformed. In the present invention, it is preferable to carefully controlthe temperature of the substrate during the formation of the layer sothat A--(Si_(x) C_(y) O_(z))_(t) H_(u) having the intended propertiescan be formed according to desire.

In order to effectively achieve the object of the present invention, thetemperature of the substrate during the formation of the surface layer104 is appropriately selected from the optimum temperature range for themethod of forming the surface layer 104. The temperature of thesubstrates is generally 50° to 400° C., preferably 100° to 350° C. It isadvantageous for forming the surface layer 104 to employ the glowdischarge process or the sputtering process because the precise controlof the component ratios of the constituent atoms of the layer and thecontrol of the thickness of the layer are relatively easy, as comparedwith other processes. However, when the surface layer 104 is formed bythe above process, the discharge power and gas pressure during theformation of the layer are important factors which influence theproperties of A--(Si_(x) C_(y) O_(z))_(t) H_(u) formed, like thetemperature of the substrate.

The condition of the discharge power for effectively forming, with highproductivity, A--(Si_(x) C_(y) O_(z))_(t) H_(u) having properties whichenable the achievement of the object of the invention is generally 10 to5000 W, preferably 20 to 2000 W, per substrate. In the RF dischargeprocess, the gas pressure in the deposition chamber is generally 0.01 to2 Torr, preferably 0.1 to 1 Torr. In the microwave discharge process,the gas pressure is generally 0.2 to 100 mTorr, preferably about 1 to 50mTorr.

Although the preferable numerical ranges of the temperature of thesubstrate and the discharge power for forming the surface layer 104 inthe invention are described above, the factors for forming the layer arenot separately determined, but the optimum value of each of the factorsfor forming each layer is preferably determined on the basis of themutual organic connection so that the surface layer of A--(Si_(x) C_(y)O_(z))_(t) H_(u) having desired properties can be formed.

The amount of the hydrogen atoms contained in the surface layer 104 ofthe electrophotographic light-receiving member in the invention isgenerally 41 to 70 atomic %, preferably 45 to 60 atomic %, of the totalconstituent atoms. When the hydrogen content is within the above ranges,the light-receiving member formed is significantly superior toconventional members in practical use and thus can be satisfactorilyused.

Namely, it is generally known that the properties of theelectrophotographic light-receiving member are adversely affected by thedefects (mainly dangling bonds of silicon and carbon atoms) which arepresent in the surface layer made of A--(Si_(x) C_(y) O_(z))_(t) H_(u).For example, the charge properties are deteriorated due to the injectionof charge from the free surface or changed due to changes in the surfacestructure in the working environment, e.g., under high humidity. Theafter image phenomenon occurs during repetitive use due to trapping ofcharge in the defects of the surface layer; the charge being injectedinto the surface layer from the photoconductive layer during coronadischarge or irradiation of light.

However, the amount of the defects in the surface layer can besignificantly decreased by controlling the hydrogen content in thesurface layer to be at least 41 atomic %. As a result, all theabove-described problems can be solved, and the electrical propertiesand high-speed continuous usability can be significantly improved, ascompared with conventional members.

On the other hand, if the hydrogen content in the surface layer exceeds70 atomic %, the hardness of the surface layer is decreased, and thusthe member cannot sufficiently resist repetitive use. It is thereforeimportant for obtaining excellent electrophotographic properties tocontrol the hydrogen content in the surface layer so that the content iswithin the above range. The hydrogen content in the surface layer can becontrolled by using the flow rate of H₂ gas, the temperature of thesubstrate, the discharge power, the gas pressure or the like.

If the atomic composition of the surface layer in the present inventionis expressed by the formula A--(Si_(q) C_(r) O_(s))_(t) H_(u), it ispreferable that q is 0.1 to 0.4, r is 0.4 to 0.7, s is 0.05 to 0.2(wherein q+r+s=1), t is 0.3 to 0.59, u is 0.41 to 0.7 (wherein t+u=1).In the present invention, however, any atoms other than the above atomscan be contained in the surface layer so far as the contents are low (1atomic % or less).

If the composition of the surface layer is beyond the above ranges, anyone of the strength, transparency, durability and weathering resistanceof the surface layer deteriorates, and the effects of the presentinvention are significantly decreased.

In the present invention, the bonding state of silicon atoms in thesurface layer is a very important factor. In order to obtain the objectsof the invention, the content of the silicon atoms each having at leastone bond to a carbon atom is within the range of 50 to 100%, preferably60 to 100%, and more preferably 70 to 100%, of the total number ofsilicon atoms in the surface layer, and the content of the silicon atomseach having at least one bond to an oxygen atom is preferably within therange of 10 to 30% of the total number of silicon atoms in the surfacelayer.

If the bonding state is beyond any one of the above ranges, the effectof the present invention, particularly, the effect of preventing tonerfilming, deteriorates.

In addition, the content of carbon atoms each having at least one bondto an oxygen atom is within the range of 10 to 30% of the total numberof carbon atoms in the surface layer so that the objects of theinvention, particularly, the object of preventing toner filming, can bemore satisfactorily achieved.

In the present invention, the numerical range of the thickness of thelayer is an important factor for effectively achieving the object of theinvention. Although any numerical range can be selected as the range ofthe thickness of the surface layer (or the surface-side region) 104 madeof A--(Si_(q) C_(r) O_(s))_(t) H_(u) which satisfies the above relationsaccording to the desired properties, a preferable range is 10 to 500 Å.Namely, if the thickness is less than 10 Å, the objects of the presentinvention are insufficiently obtained, and the surface layer issometimes lost due to abrasion or the like during the use of thelight-receiving member. If the thickness exceeds 500 Å, theelectrophotographic properties sometimes deteriorate, for example, theresidual potential is increased.

In the present invention, it is also effective for further improving theproperties such as the chargeability or the like by providing a blockinglayer (lower surface layer)or a blocking region (lower surface region),which is made of SiC (H, X) and which contains oxygen atoms in a reducedamount, between the photoconductive layer and the surface layer or inthe surface layer.

In the electrophotographic light-receiving member of the presentinvention, an adhesive layer made of Si₃ N₄, SiO₂, SiO or a non-singlecrystal material containing at least one of hydrogen and halogen atoms,at least one of nitrogen and oxygen atoms and a silicon atom may beprovided between the substrate 101 and the photoconductive layer 103 forthe purpose of further improving the adhesion therebetween, like theabove-described example.

In the embodiment of the surface layer 104 made of A--(Si_(q) C_(r)O_(s))_(t) H_(u), the component ratios may be gradually changed so thatno clear interface is present between the photoconductive layer 103 andthe surface layer 104 to obtain the surface layer 104 having the desiredcomponent ratios.

As a matter of course, in this embodiment, the production conditions areselected so as to satisfy each of the above requirements.

A description will be now made of the method of producing thephotoconductive member by the microwave discharge process.

FIGS. 6 and 7 show the apparatus for producing the electrophotographiclight-receiving member by the microwave discharge process using acylindrical substrate. In the drawings, reference numeral 1101 denotes areactor having a structure which can be made airtight under vacuum.Reference numeral 1102 denotes a microwave introducing dielectric windowwhich efficiently transmits microwave power to the reactor 1101, andwhich is made of a material (for example, quartz glass, alumina ceramicsor the like) which can hold the airtight vacuum state. Reference numeral1103 denotes a waveguide for transmitting microwave power whichcomprises a rectangular portion extended from a microwave power sourceto a position near the reactor 1101 and a cylindrical portion insertedinto the reactor 1101. The waveguide 1103 is connected to the microwavepower source (not shown) together with a stab tuner (not shown) and anisolator (not shown). The dielectric window 1102 is hermetically sealedto the inner wall of the cylindrical portion of the waveguide 1103 so asto hold the atmosphere in the reactor 1101. Reference numeral 1104denotes an exhaust pipe having an end opened to the reactor 1101 and theother end communicating with an exhauster (not shown). Reference numeral1106 denotes a discharge space surrounded by substrates 1105. A powersource 1111 is a DC power source (bias power source) and is electricallyconnected to an electrode 1112 for the purpose of applying a DC voltageto the bias electrode 1112.

The electrophotographic light-receiving member is produced by the aboveproduction apparatus according to the method below. The air in thereactor 1101 is exhausted by a vacuum pump (not shown) through theexhaust pipe 1104 so that the pressure in the reactor 1101 is adjustedto 1×10⁻⁷ Torr or less. Each of the substrates 1105 is then heated to apredetermined temperature by a heater 1107. Raw material gases for afirst layer region is introduced through gas introducing means (notshown). Namely, raw material gases such as silane gas as raw materialgas for A--Si (H,X), diborane gas as doping gas and helium gas asdilution gas are introduced into the reactor 1101. At the same time, amicrowave with a frequency of 2.45 GHz is generated from the microwavepower source (not shown) and introduced into the reactor 1101 throughthe microwave introducing dielectric window 1102 through the waveguide1103. A DC voltage is applied to the bias electrode 1112 from the DCpower source 1111 electrically connected to the bias electrode 1112 inthe discharge space 1106 so as to be applied to the substrates 1105. Theraw material gases in the discharge space 1106 surrounded by thesubstrates 1105 are thus excited and dissociated by the energy of themicrowave. The substrates 1105 are stationarily subjected to ion impactby the electrical field between the bias electrode 1112 and thesubstrates 1105 to form a first layer region on the surface of each ofthe substrate 1105. During this time, each of the substrates 1105 isrotated around the axis in the direction of the generating line thereofby using a motor for rotating a rotation shaft 1109 on which each of thesubstrates 1105 is installed so that a deposited film layer is uniformlyformed over the whole periphery of the substrate 1105.

When a second layer region is formed on the thus-formed first layerregion, discharge is started by the same method as that employed forforming the first layer region with the exception that the compositionof raw material gas introduced into the reactor 1101 is changed to, forexample, silane gas, methane gas, tetramethylsilane gas and, ifrequired, hydrogen gas as dilution gas.

The amount of carbon atoms contained in the second layer region formedcan be controlled by, for example, changing the ratio between the flowrates of silane gas and methane gas which are introduced into thedischarge space. The state of bonding of silicon atoms can bearbitrarily controlled by displacing silane gas and methane gas bytetramethylsilane gas. In addition, the bonding state can be moreeffectively controlled by changing the bias voltage applied to thedischarge space. The amount of the hydrogen atoms contained in thesecond layer region can be controlled according to desire by, forexample, arbitrarily changing the flow rate of hydrogen gas introducedinto the discharge space.

When a second layer region containing oxygen atoms is formed on thefirst layer region formed, discharge is started by the same method asthat employed for forming the first layer region with the exception thatthe composition of raw material gas introduced into the reactor 1101 ischanged to, for example, silane gas, methane gas, tetramethylsilane gas,oxygen gas, nitrogen monoxide gas and, if required, hydrogen gas asdilution gas.

The amount of carbon atoms or oxygen atoms contained in the second layerregion formed can be controlled by, for example, changing the ratioamong the flow rates of silane gas, methane gas and oxygen gas which areintroduced into the discharge space. The state of bonding of siliconatoms can be arbitrarily controlled by displacing silane gas and methanegas by tetramethylsilane gas and oxygen gas by nitrogen monoxide gas. Inaddition, the bonding state can be more effectively controlled bychanging the bias voltage applied to the discharge space. The amount ofthe hydrogen atoms contained in the second layer region can becontrolled according to desire by, for example, arbitrarily changing theflow rate of hydrogen gas introduced into the discharge space.

EXAMPLE 1

An electrophotographic light-receiving member was formed on a planishedaluminum cylinder by using the production apparatus shown in FIGS. 6 and7 according to the formation conditions shown in Table 1. In addition,separate surface layers were formed on the same cylinder by using thesame apparatus as that shown in FIGS. 6 and 7. The light-receivingmember (referred to as "drum" hereinafter) was set in anelectrophotographic apparatus (produced by converting NPP7550manufactured by Canon Corp. for tests in the invention). The initialelectrophotographic properties such as chargeability, sensitivity, imageflowing in high-humidity environment (atmospheric temperature: 30° C.,humidity: 90%), residual potential, ghost, image defect and the likewere evaluated under various conditions. The drum was then subjected anendurance test in which printing on 500,000 sheets was performed atatmospheric temperature of 35° C. and humidity 95% without using drumheating means such as a drum heater or the like, and the same evaluationas that performed in the initial stage was performed. The occurrence ofdamage on the drum which was caused by the endurance test was alsoevaluated. If required, the amount of the atoms on the surface andbonding state of the atoms were also analyzed by ESCA.

A plurality of pieces were cut from portions of each of the separatesurface layers (referred to as "samples" hereinafter) corresponding tothe upper and lower portions of an image portion and subjected toquantitative analysis of the silicon, carbon, oxygen and hydrogen atoms,which were contained in the layer, by Auger, SIMS and organic elementalanalysis, as occasion demands. If required, the amount of the atoms inthe surface and the bonding state were also analyzed by ESCA.

FIGS. 8 and 9 show the ESCA spectra obtained the analysis.

Tables 2 and 3 show the results of the evaluation and the initial valuesobtained by quantitative analysis. As seen from Table 2, remarkablesuperiority was confirmed in the properties after the endurance test ina high-humidity environment.

                  TABLE 1                                                         ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      20   sccm                                    NO              3      sccm      0    sccm                                    CH.sub.4        0      sccm      0    sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      100  sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         100    sccm      500  sccm                                    Pressure        10     mtorr     10   mtorr                                   Microwave Power 1000   W         1000 W                                       Bias Voltage    100    V         100  V                                       Thickness       25     μm     0.5  μm                                   ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                        Initial          Chargeability                                                                              ⊚                                Properties       Sensitivity  ⊚                                                 Image Flowing                                                                              ⊚                                                 Residual Potential                                                                         ⊚                                                 Ghost        ◯                                                    Image Defect ⊚                                Properties After Chargeability                                                                              ⊚                                Endurance in     Sensitivity  ⊚                                High-Humidity    Image Flowing                                                                              ⊚                                Environment      Residual Potential                                                                         ⊚                                                 Ghost        ◯                                                    Image Defect ◯                                                    Drum Damage  ⊚                                ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 3                                                         ______________________________________                                                      Component Ratio                                                 Element       (at %)                                                          ______________________________________                                        Si (total)    13.1                                                            Si (Si--C)    10.8                                                            C (total)     28.9                                                            C (C--Si)     11.6                                                            H             58.0                                                            ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  C (C--Si) Component ratio of C atoms having C--Si bonding.               

COMPARATIVE EXAMPLE 1

A drum and a sample were formed by the same apparatus and method asthose employed in Example 1 with the exception that the formationconditions were changed as shown in Table 4 and then subjected to thesame evaluation. The results obtained are shown in Tables 5 and 6.

As seen from Table 5, it was confirmed that Comparative Example 1 isinferior to Example 1 in various evaluation items.

                  TABLE 4                                                         ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      70   sccm                                    NO              3      sccm      0    sccm                                    CH.sub.4        0      sccm      300  sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      0    sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         100    sccm      700  sccm                                    Pressure        10     mtorr     11   mtorr                                   Microwave Power 1000   W         1000 W                                       Bias Voltage    100    V         100  V                                       Thickness       25     μm     0.5  μm                                   ______________________________________                                    

                  TABLE 5                                                         ______________________________________                                        Initial          Chargeability                                                                              ⊚                                Properties       Sensitivity  ◯                                                    Image blurring                                                                             ⊚                                                 Residual Potential                                                                         ◯                                                    Ghost        ◯                                                    Image Defect ⊚                                Properties After Chargeability                                                                              ◯                                   Endurance in     Sensitivity  Δ                                         High-Humidity    Image blurring                                                                             X                                               Environment      Residual Potential                                                                         X                                                                Ghost        Δ                                                          Image Defect ◯                                                    Drum Damage  ◯                                   ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 6                                                         ______________________________________                                                      Component Ratio                                                 Element       (at %)                                                          ______________________________________                                        Si (total)    12.8                                                            Si (Si--C)    3.8                                                             C (total)     28.4                                                            C (C--Si)     3.4                                                             H             58.8                                                            ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  C (C--Si) Component ratio of C atoms having C--Si bonding.               

EXAMPLE 2 AND COMPARATIVE EXAMPLE 2

A plurality of drums and analytical samples were prepared under the sameconditions as those in Example 1 with the exception that the conditionsfor formation of the surface layer were changed as shown in Table 7. Asa result of the same evaluation and analysis as those in Example 1, theresults shown in Tables 8 and 9 were obtained.

                  TABLE 7                                                         ______________________________________                                                                              Comparative                                      2-1  2-2    2-3    2-4  2-5  Example 2                               ______________________________________                                        Raw Gas Flow                                                                  Rate (sccm)                                                                   SiH.sub.4  30     35     40   45   50   55                                    CH.sub.4   60     90     120  150  180  210                                   Si (CH.sub.3).sub.4                                                                      80     70     60   50   40   30                                    H.sub.2    550    550    600  600  600  650                                   Pressure (mtorr)                                                                         10     10     11   11   11   11                                    Microwave  1000   1000   1000 1000 1000 1000                                  Power                                                                         Bias Voltage (V)                                                                         100    100    100  100  100  100                                   Thickness (μm)                                                                        0.5    0.5    0.5  0.5  0.5  0.5                                   ______________________________________                                    

                  TABLE 8                                                         ______________________________________                                                                              Comparative                                      2-1  2-2    2-3    2-4  2-5  Example 2                               ______________________________________                                        Initial Properties                                                            Chargeability                                                                            ⊚                                                                     ⊚                                                                     ⊚                                                                   ⊚                                                                   ⊚                                                                   ⊚                      Sensitivity                                                                              ⊚                                                                     ⊚                                                                     ⊚                                                                   ◯                                                                      ⊚                                                                   ◯                         Image Flowing                                                                            ⊚                                                                     ⊚                                                                     ⊚                                                                   ⊚                                                                   ⊚                                                                   ◯                         Residual Potential                                                                       ⊚                                                                     ⊚                                                                     ⊚                                                                   ⊚                                                                   ⊚                                                                   ◯                         Ghost      ◯                                                                        ⊚                                                                     ⊚                                                                   ⊚                                                                   ◯                                                                      ◯                         Image Defect                                                                             ⊚                                                                     ◯                                                                        ⊚                                                                   ⊚                                                                   ◯                                                                      ◯                         Properties After Endurance                                                    in High Humidity Environment                                                  Chargeability                                                                            ⊚                                                                     ⊚                                                                     ⊚                                                                   ◯                                                                      ◯                                                                      ◯                         Sensitivity                                                                              ⊚                                                                     ⊚                                                                     ⊚                                                                   ◯                                                                      ◯                                                                      Δ                               Image Flowing                                                                            ⊚                                                                     ◯                                                                        ◯                                                                      Δ                                                                            Δ                                                                            X                                     Residual Potential                                                                       ⊚                                                                     ◯                                                                        ◯                                                                      Δ                                                                            Δ                                                                            X                                     Ghost      ◯                                                                        ◯                                                                        ⊚                                                                   ◯                                                                      ◯                                                                      Δ                               Image Defect                                                                             ◯                                                                        ◯                                                                        ◯                                                                      ◯                                                                      ◯                                                                      ◯                         Drum Damage                                                                              ⊚                                                                     ⊚                                                                     ⊚                                                                   ⊚                                                                   ⊚                                                                   ◯                         ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 9                                                         ______________________________________                                        Component Ratio (at %)                                                                                                Comparative                           Element 2-1     2-2    2-3   2-4  2-5   Example 2                             ______________________________________                                        Si (total)                                                                            13.5    12.8   13.0  12.9 12.1  13.5                                  Si (Si--C)                                                                            9.7     8.6    8.0   7.4  6.2   6.0                                   C (total)                                                                             29.3    28.9   29.2  28.0 27.8  30.3                                  C (C--Si)                                                                             8.9     8.2    7.7   7.2  6.3   6.1                                   H       57.2    58.3   57.8  59.1 60.1  56.2                                  ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  C (C--Si) Component ratio of C atoms having C--Si bonding.               

EXAMPLE 3 AND COMPARATIVE EXAMPLES 3 AND 4

A plurality of drums and analytical samples were prepared under the sameconditions as those in Example 1 with the exception that the conditionsfor formation of the surface layer were changed as shown in Table 10. Asa result of the same evaluation and analysis as those in Example 1, theresults shown in Tables 11 and 12 were obtained.

                  TABLE 10                                                        ______________________________________                                               Com-                            Com-                                          parative                        parative                                      Example 3                                                                             3-1    3-2    3-3  3-4  Example 4                              ______________________________________                                        Raw Gas                                                                       Flow Rate                                                                     (sccm)                                                                        SiH.sub.4                                                                              30        30     30   15   10   5                                    CH.sub.4 0         20     40   200  200  300                                  Si (CH.sub.3).sub.4                                                                    80        80     80   40   25   14                                   H.sub.2  450       550    550  600  600  650                                  Pressure 10        10     11   11   11   11                                   (mtorr)                                                                       Microwave                                                                              1000      1000   1000 1000 1000 1000                                 Power                                                                         Bias Voltage                                                                           100       100    100  100  100  100                                  (V)                                                                           Thickness                                                                              0.5       0.5    0.5  0.5  0.5  0.5                                  (μm)                                                                       ______________________________________                                    

                  TABLE 11                                                        ______________________________________                                                 Comparative                  Comparative                                      Example 3                                                                              3-1   3-2   3-3 3-4 Example 4                               ______________________________________                                        Initial Properties                                                            Chargeability                                                                            X          Δ                                                                             ◯                                                                     ◯                                                                     ◯                                                                     ◯                         Sensitivity                                                                              X          Δ                                                                             ◯                                                                     ◯                                                                     Δ                                                                           X                                     Image blurring                                                                           Δ    ◯                                                                       ◯                                                                     ⊚                                                                  ⊚                                                                  ◯                         Residual Potential                                                                       ◯                                                                            ◯                                                                       ⊚                                                                  ◯                                                                     Δ                                                                           X                                     Ghost      X          Δ                                                                             ⊚                                                                  ◯                                                                     ⊚                                                                  ◯                         Image Defect                                                                             ◯                                                                            ⊚                                                                    ◯                                                                     ⊚                                                                  ◯                                                                     ◯                         Properties After Endurance                                                    in High Humidity Environment                                                  Chargeability                                                                            X          Δ                                                                             ◯                                                                     ◯                                                                     ◯                                                                     ◯                         Sensitivity                                                                              X          Δ                                                                             ◯                                                                     ◯                                                                     Δ                                                                           X                                     Image blurring                                                                           X          Δ                                                                             ◯                                                                     ⊚                                                                  ◯                                                                     ⊚                      Residual Potential                                                                       Δ    ◯                                                                       ◯                                                                     ◯                                                                     Δ                                                                           X                                     Ghost      X          Δ                                                                             ◯                                                                     ◯                                                                     ◯                                                                     Δ                               Image Defect                                                                             ◯                                                                            ◯                                                                       ◯                                                                     ◯                                                                     ◯                                                                     ◯                         Drum Damage                                                                              X          Δ                                                                             ◯                                                                     ◯                                                                     Δ                                                                           X                                     ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 12                                                        ______________________________________                                        Component Ratio (at %)                                                                Com-                             Com-                                         parative                         parative                             Element Example 3 3-1    3-2   3-3  3-4  Example 4                            ______________________________________                                        Si (total)                                                                            26.0      22.2   19.2  8.1  5.6  4.0                                  Si (Si--C)                                                                            18.5      15.8   13.7  5.8  4.0  2.9                                  C (total)                                                                             15.9      21.6   25.5  39.6 37.3 46.2                                 C (C--Si)                                                                             15.1      14.8   12.9  5.9  4.1  3.0                                  H       58.1      56.2   55.3  52.3 57.1 49.8                                 ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  C (C--Si) Component ratio of C atoms having C--Si bonding.               

EXAMPLE 4

A plurality of drums were prepared under the same conditions as those inExample 1 with the exception that the conditions for formation of thephotoconductive layer were changed as shown in Table 13. As a result ofthe same evaluation as that in Example 1, the same good results as thoseobtained in Example 1 were obtained.

                  TABLE 13                                                        ______________________________________                                                  Layer Structure                                                                 Charge                                                                        Injection  Charge     Charge                                      Film-Forming                                                                              Inhibition Transport  Generating                                  Condition   Layer      Layer      Layer                                       ______________________________________                                        Raw Gas                                                                       Flow Rate                                                                     SiH.sub.4   350    sccm    350  sccm  350  sccm                               He          100    sccm    100  sccm  100  sccm                               CH.sub.4    35     sccm    35   sccm  0    sccm                               B.sub.2 H.sub.6                                                                           1000   ppm     0    ppm   0    ppm                                Pressure    11     mtorr   11   mtorr 10   mtorr                              Microwave Power                                                                           1000   W       1000 W     1000 W                                  Bias Voltage                                                                              100    V       100  V     100  V                                  Thickness   3      μm   20   μm 5    μm                              ______________________________________                                    

EXAMPLE 5

A photoconductive layer was formed by the RF discharge process under theconditions shown in Table 14, and the surface layer as that in Example 1was then formed by using the production apparatus shown in FIGS. 6 and7. When the thus-formed drum was subjected to the same evaluation asthat in Example 1, the same good results as those obtained in Example 1were obtained.

                  TABLE 14                                                        ______________________________________                                                      Layer Structure                                                                 Charge                                                                        Injection        Photo-                                       Film-Forming    Inhibition       conductive                                   Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       250    sccm      350  sccm                                    He              250    sccm      350  sccm                                    CH.sub.4        0      sccm      0    sccm                                    B.sub.2 H.sub.6 1000   ppm       0    ppm                                     Pressure        0.3    torr      0.5  torr                                    PF Power        300    W         400  W                                       Thickness       3      μm     25   μm                                   ______________________________________                                    

EXAMPLE 6

An electrophotographic light-receiving member was formed on a planishedaluminum cylinder by using the production apparatus shown in FIGS. 6 and7. During this formation, the conditions for forming a photoconductivelayer and a surface layer were as shown in Table 15. However, in orderto change the ratio of silicon atoms combined with carbon atoms in thesurface layer, the flow rates of silane gas, methane gas andtetramethylsilane gas were changed so that light-receiving members(referred to as "drums" hereinafter) were respectively formed under theconditions shown by the six samples 1A to 1F in Table 16. In addition,separate surface layers were formed on the same cylinder as thatdescribed above by using the same apparatus as that shown in FIGS. 6 and7.

Each of the drums was set in an electrophotographic apparatus (producedby remodeling NP7750 manufactured by Canon Corp. for tests in theinvention) and evaluated with respect to initial electrophotographicproperties such as chargeability, sensitivity, image flowing in ahigh-humidity environment (atmospheric temperature: 30° C., humidity:85%), residual potential, ghost, image defects and the like. Each of thedrum was then subjected to an endurance test in which 500000 sheets wereprinted without using drum heating means such as a drum heater or thelike in a high-humidity environment at atmospheric temperature of 32° C.and humidity of 90% and then evaluated with respect to the sameproperties as those in the initial stage. The occurrence of tonerfilming on the drum surface was also evaluated after the endurance test.The toner used for evaluation is a heat fixing toner containing as amain component a polyester resin.

A plurality of pieces were cut from portions of each of the separatesurface layers (referred to as "samples" hereinafter) which correspondedwith the upper and lower portions of the image portion and subjected toquantitative analyses of the silicon atoms, carbon atoms, oxygen atomsand hydrogen atoms contained in the layer by using Auger, SIMS andorganic elemental analyses. The amount of atoms and bonding statethereof were also analyzed by ESCA.

The results of evaluation and the initial quantitative analytical valuesare shown in Tables 17 and 18. In Table 18, it is assumed that the totalof silicon, carbon, oxygen and hydrogen atoms is 100 atomic %. It wasfound from the results that there is present a proper ratio of siliconatoms combined with carbon atoms. Each of the drums showed significantsuperiority in the properties after the endurance test was conducted ina high-humidity environment.

                  TABLE 15                                                        ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       300    sccm      •                                                                            sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      •                                                                            sccm                                    CH.sub.4        0      sccm      •                                                                            sccm                                    O.sub.2         0      sccm      14   sccm                                    NO              3      sccm      12   sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         800    sccm      1000 sccm                                    Pressure        14     mtorr     14   mtorr                                   Microwave Power 1200   W         1200 W                                       Bias Voltage    60     V         60   V                                       Thickness       25     μm     0.03 μm                                   ______________________________________                                         • Conditions shown in Table 16                                     

                  TABLE 16                                                        ______________________________________                                                    Sample Name                                                       Raw Gas       1A    1B      1C  1D    1E   1F                                 ______________________________________                                        Si H.sub.4 (sccm)                                                                           30    35      40  50    60   70                                 Si (CH.sub.3).sub.4 (sccm)                                                                  80    70      60  40    20    0                                 CH.sub.4 (sccm)                                                                             30    60      90  150   210  270                                ______________________________________                                    

                  TABLE 17                                                        ______________________________________                                                     Sample Name                                                      Evaluation Item                                                                              1A    1B      1C  1D    1E  1F                                 ______________________________________                                        Properties                                                                    Chargeability  ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Sensitivity    ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Image Blurring ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Residual Potential                                                                           ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Ghost          ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Image Defect   ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Properties After                                                              Endurance in High-                                                            Humidity Environment                                                          Chargeability  ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Sensitivity    ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Image Blurring ⊚                                                                    ⊚                                                                      ⊚                                                                  ◯                                                                       Δ                                                                           Δ                            Residual Potential                                                                           ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Ghost          ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Image Defect   ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Toner Filming  ⊚                                                                    ⊚                                                                      ◯                                                                     Δ                                                                             X   X                                  ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 18                                                        ______________________________________                                                Component Ratio (at %)                                                Element   1A     1B       1C   1D     1E   1F                                 ______________________________________                                        Si (total)                                                                              11.4   11.6     12.0 12.7   13.0 13.2                               Si (Si--C)                                                                              10.4   8.5      7.2  6.5    5.5  3.3                                Si (Si--O)                                                                              2.4    2.8      2.8  3.0    2.8  3.0                                C (total) 25.1   23.9     24.0 21.2   21.0 20.8                               O (total) 5.5    5.7      5.5  6.0    5.8  6.0                                H         58.0   58.8     58.5 60.1   60.2 60.0                               ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  Si (Si--O) Component ratio of Si atoms having Si--O bonding.             

EXAMPLE 7

An electrophotographic light-receiving member was formed by using theproduction apparatus shown in FIGS. 6 and 7 according to the sameprocedure as that employed in Example 6. The conditions for forming aphotoconductive layer and a surface layer were as shown in Table 19. Inorder to change the ratio of the silicon atoms combined with oxygenatoms in the surface layer, the flow rates of nitrogen monoxide gas andoxygen gas were changed so that drums were respectively formed under theconditions shown by the six samples 1G to 1L in Table 20. In addition,separate surface layers were formed on the same cylinder as that used inExample 6 by using the same apparatus as shown in FIGS. 6 and 7.

The drums and samples were evaluated and analyzed in the same manner asin Example 6.

The results of evaluation and initial quantitative analytical values areshown in Tables 21 and 22. In Table 22, it is assumed that the total ofsilicon, carbon, oxygen and hydrogen atoms is 100 atomic%. It was foundfrom the results that there is a proper ratio of the oxygen atomscombined with silicon atoms. Each of the drums showed remarkablesuperiority in the properties after the endurance test conducted in ahigh-humidity environment.

                  TABLE 19                                                        ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      35   sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      70   sccm                                    CH.sub.4        0      sccm      60   sccm                                    O.sub.2         0      sccm      •                                                                            sccm                                    NO              3      sccm      •                                                                            sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         800    sccm      1000 sccm                                    Pressure        14     mtorr     14   mtorr                                   Microwave Power 1200   W         1200 W                                       Bias Voltage    60     V         60   V                                       Thickness       25     μm     0.03 μm                                   ______________________________________                                         • Conditions shown in Table 20                                     

                  TABLE 20                                                        ______________________________________                                                 Sample Name                                                          Raw Gas    1G    1H       1I  1J     1K  1L                                   ______________________________________                                        O.sub.2 (sccm)                                                                            0     6       10  16     18  20                                   NO (sccm)  40    28       20   8      4   0                                   ______________________________________                                    

                  TABLE 21                                                        ______________________________________                                                     Sample Name                                                      Evaluation Item                                                                              1G    1H      1I  1J    1K  1L                                 ______________________________________                                        Initial Properties                                                            Chargeability  ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Sensitivity    ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Image Blurring ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Residual Potential                                                                           ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Ghost          ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Image Defect   ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Properties After                                                              Endurance in High-                                                            Humidity Environment                                                          Chargeability  ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Sensitivity    ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Image Blurring ◯                                                                       ⊚                                                                      ⊚                                                                  ⊚                                                                    ◯                                                                     Δ                            Residual Potential                                                                           ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Ghost          ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Image Defect   ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Toner Filming  X     Δ ⊚                                                                  ⊚                                                                    Δ                                                                           X                                  ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 22                                                        ______________________________________                                        Component Ratio (at %)                                                        Element 1G      1H     1I    1B   1J    1K   1L                               ______________________________________                                        Si (Total)                                                                            11.9    11.8   11.6  11.6 10.9  10.8 10.7                             Si (Si--C)                                                                            8.9     8.8    9.0   8.5  8.7   8.2  7.9                              Si (Si--O)                                                                            4.5     4.0    3.3   2.8  1.3   0.8  0.5                              C (total)                                                                             23.9    24.4   25.0  23.9 26.6  27.2 28.0                             O (total)                                                                             6.0     5.8    5.7   5.7  5.0   4.8  4.4                              H       58.2    58.0   57.7  58.8 57.5  57.2 56.9                             ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  Si (Si--O) Component ratio of Si atoms having Si--O bonding.             

EXAMPLE 8

A charge injection inhibition layer, a photoconductive layer and a lowersurface layer were formed on a substrate by using the productionapparatus shown in FIGS. 6 and 7 under the conditions shown in Table 23,and a surface layer was then formed under the same conditions as thosefor Sample 1A of Example 6.

As a result of evaluation of the drum in the same manner as in Example6, good results were obtained, like the drum formed under the conditionsfor Sample 1A of Example 6.

                  TABLE 23                                                        ______________________________________                                                  Layer Structure                                                                 Charge                                                                        Injection  Photo-     Lower                                       Film-Forming                                                                              Inhibition conductive Surface                                     Condition   Layer      Layer      Layer                                       ______________________________________                                        Raw Gas                                                                       Flow Rate                                                                     SiH.sub.4   350    sccm    350  sccm  70   sccm                               He          100    sccm    100  sccm  100  sccm                               CH.sub.4    35     sccm    0    sccm  350  sccm                               B.sub.2 H.sub.6                                                                           1000   ppm     0    ppm   0    ppm                                Pressure    11     mtorr   10   mtorr 12   mtorr                              Microwave Power                                                                           1000   W       1000 W     1000 W                                  Bias Voltage                                                                              100    V       100  V     100  V                                  Thickness   3      μm   20   μm 0.5  μm                              ______________________________________                                    

EXAMPLE 9

A drum was formed under the conditions shown in Table 24 in which theconditions for forming a photoconductive layer were changed from Example6, and a surface layer was then formed under the same conditions asthose in Sample 1B of Example 6.

As a result of evaluation of the drum in the same manner as in Example6. good results were obtained, like the drum formed under the conditionsfor Sample 1B of Example 6.

                  TABLE 24                                                        ______________________________________                                                  Layer Structure                                                                 Charge                                                                        Injection  Charge     Charge                                      Film-Forming                                                                              Inhibition Transport  Generating                                  Condition   Layer      Layer      Layer                                       ______________________________________                                        Raw Gas                                                                       Flow Rate                                                                     SiH.sub.4   350    sccm    350  sccm  350  sccm                               He          100    sccm    100  sccm  100  sccm                               CH.sub.4    35     sccm    35   sccm  0    sccm                               B.sub.2 H.sub.6                                                                           1000   ppm     0    ppm   0    ppm                                Pressure    11     mtorr   11   mtorr 10   mtorr                              Microwave Power                                                                           1000   W       1000 W     1000 W                                  Bias Voltage                                                                              100    V       100  V     100  V                                  Thickness   3      μm   20   μm 5    μm                              ______________________________________                                    

EXAMPLE 10

A photoconductive layer was formed by the RF discharge process under theconditions shown in Table 25, and a surface layer was then formed byusing the production apparatus shown in FIGS. 6 and 7 under the sameconditions as those for Sample 1B of Example 6.

As a result of evaluation of the thus-formed drum in the same manner asin Example 6, good results were obtained, like the drum formed under theconditions for Sample 1B of Example 6.

                  TABLE 25                                                        ______________________________________                                                      Layer Structure                                                                 Charge                                                                        Injection        Photo-                                       Film-Forming    Inhibition       conductive                                   Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       250    sccm      350  sccm                                    He              250    sccm      35   sccm                                    CH.sub.4        0      sccm      0    sccm                                    B.sub.2 H.sub.6 1000   ppm       0    ppm                                     Pressure        0.3    torr      0.5  torr                                    RF Power        300    W         400  W                                       Thickness       3      μm     25   μm                                   ______________________________________                                    

EXAMPLE 11

The same photoconductive layer as that formed in Example 6 was formed,and a surface layer was then formed under the same conditions as thosefor Sample 1B of Example 6, while the thickness was changed from 5Å to 1μm.

As a result of evaluation of the thus-formed drum in the same manner asin Example 6, good results were obtained from samples comprising thesurface layers having thicknesses from 10Å to 500Å, like the drum formedunder the conditions for Sample 1B of Example 6. The advantages of thepresent invention were thus confirmed.

EXAMPLE 12

The same evaluations as that performed in Examples 6 to 11 wereperformed, while the contents of silicon, carbon, oxygen and hydrogenatoms in the surface layer were changed. As a result, it was confirmedthat assuming that the composition of a surface layer is (Si_(x) C_(y)O_(z))_(t) H_(u) (wherein x+y+z=1, t+u=1), when 0.1 ≦x≦0.4, 0.4≦y≦0.7,0.05≦z≦0.2, 0.3≦t≦0.59 and 0.41≦u≦0.7, the drum of the present inventionshows good electrophotographic properties. The advantages of the presentinvention were thus confirmed.

EXAMPLE 13

An electrophotographic light-receiving member was formed on a planishedaluminum cylinder by using the production apparatus shown in FIG. 6. Theconditions for forming a photoconductive layer and a surface layer wereas shown in Table 26. However, in order to change the ratio of siliconatoms combined with carbon atoms in the surface layer, the flow rates ofsilane gas, methane gas and tetramethylsilane gas were changed so thatlight-receiving members (referred to as "drum" hereinafter) wererespectively formed under the conditions shown by the six Samples 2A to2F in Table 27. In addition, separate surface layers were formed on thesame cylinder as that described above by using the same apparatus shownin FIG. 6.

Each of the thus-formed drums were set in an electrophotographicapparatus (produced by demodeling NP7550 manufacture by Canon Corp. fortests in the invention) and evaluated with respect to initialelectrophotographic properties such as chargeability, sensitivity, imageflowing in a high-humidity environment (atmospheric temperature: 30° C.,humidity: 90%), residual potential, ghost, image defects and the likeunder various conditions. Each of the drums was then subjected to anendurance test in which 500,000 sheets were printed without using drumheating means such as a drum heater or the like in a high-humidityenvironment at atmospheric temperature of 30° C. and humidity of 97% andthen evaluated in the same manner as that in the initial stage. Theoccurrence of toner filming was also evaluated after the endurance test.The toner used was a pressure fixing toner containing as a maincomponent a polyethylene resin.

A plurality of pieces were cut from portions of each of the separatesurface layers (referred to as "samples" hereinafter) which were formedon the cylinder, corresponding to upper and lower portions of the imageportion and then subjected to quantitative analyses of the silicon,carbon, oxygen and hydrogen atoms contained in the layer by Auger, SIMSand organic elemental analysis. The amount of atoms and bonding statethereof were also analyzed by ESCA.

The results of evaluation and the initial quantitatively analyticalvalues are shown in Tables 28 and 29. The results revealed that there isa proper ratio of silicon atoms combined with carbon atoms. Each of thedrums showed significant superiority in the properties after theendurance test in a high-humidity environment.

                  TABLE 26                                                        ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      •                                                                            sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      •                                                                            sccm                                    CH.sub.4        0      sccm      •                                                                            sccm                                    (CH.sub.3).sub.2 O                                                                            0      sccm      20   sccm                                    O.sub.2         0      sccm      7    sccm                                    NO              3      sccm      6    sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         100    sccm      400  sccm                                    Pressure        8      mtorr     9    mtorr                                   Microwave Power 1000   W         900  W                                       Bias Voltage    100    V         120  V                                       Thickness       25     μm     0.03 μm                                   ______________________________________                                         • Conditions shown in Table 27                                     

                  TABLE 27                                                        ______________________________________                                                    Sample Name                                                       Raw Gas       A     B       C   D     E    F                                  ______________________________________                                        SiH.sub.4 (sccm)                                                                            30    35      40  50    60   70                                 Si (CH.sub.3).sub.4 (sccm)                                                                  80    70      60  40    20    0                                 CH.sub.4 (sccm)                                                                              0    30      60  120   180  240                                ______________________________________                                    

                  TABLE 28                                                        ______________________________________                                                     Sample Name                                                      Evaluation Item                                                                              A     B       C   D     E   F                                  ______________________________________                                        Properties                                                                    Chargeability  ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Sensitivity    ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Image Blurring ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Residual Potential                                                                           ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Ghost          ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Image Defect   ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Properties After                                                              Endurance in High-                                                            Humidity Environment                                                          Chargeability  ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Sensitivity    ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Image Blurring ⊚                                                                    ⊚                                                                      ⊚                                                                  ◯                                                                       Δ                                                                           Δ                            Residual Potential                                                                           ⊚                                                                    ⊚                                                                      ⊚                                                                  ⊚                                                                    ⊚                                                                  ⊚                   Ghost          ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Image Defect   ◯                                                                       ◯                                                                         ◯                                                                     ◯                                                                       ◯                                                                     ◯                      Toner Filming  ⊚                                                                    ⊚                                                                      ◯                                                                     Δ                                                                             X   X                                  ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 29                                                        ______________________________________                                                Component Ratio (Atomic %)                                            Element   2A     2B       2C   2D     2E   2F                                 ______________________________________                                        Si (total)                                                                              11.6   11.7     12.1 12.2   12.5 13.0                               Si (Si--C)                                                                              10.5   8.7      7.8  6.7    5.6  3.9                                Si (Si--O)                                                                              2.5    2.7      2.6  2.9    2.9  3.0                                C (total) 24.8   23.8     25.1 24.5   22.1 22.7                               C (C--O)  5.1    5.2      5.1  4.9    5.0  5.1                                O (total) 5.8    5.7      5.5  5.3    5.7  5.5                                H         57.8   58.8     57.3 58.0   59.7 58.9                               ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  Si (Si--C) Component ratio of Si atoms having Si--O bonding.                  C (C--O) Component ratio of C atoms having C--O bonding.                 

EXAMPLE 14

Electrophotographic light-receiving members were formed by using theproduction apparatus shown in FIG. 6 according to the same procedure asthat used in Example 13. The conditions for forming a photoconductivelayer and a surface layer were as shown in Table 30. However, in orderto change the ratio of silicon atoms combined with oxygen atoms in thesurface layer, the flow rates of nitrogen monoxide gas and oxygen gaswere changed so that drums were respectively formed under the conditionsshown by the six samples 2G to 2L in Table 31. In addition, separatesurface layers were formed on the same cylinder as that used in Example13 by using the same apparatus as that shown in FIG. 6.

The thus-formed drums and samples were evaluated and analyzed by thesame method as that employed in Example 13.

The results of evaluation and initial quantitative analytical values areshown in Tables 32 and 33. It was found from the results that there is aproper ratio of silicon atoms combined with oxygen atoms. Each of thedrums showed significant superiority in the properties after theendurance test in a high-humidity environment.

                  TABLE 30                                                        ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      35   sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      70   sccm                                    CH.sub.4        0      sccm      30   sccm                                    (CH.sub.3).sub.2 O                                                                            0      sccm      20   sccm                                    O.sub.2         0      sccm      •                                                                            sccm                                    NO              3      sccm      •                                                                            sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         100    sccm      400  sccm                                    Pressure        8      mtorr     9    mtorr                                   Microwave Power 1000   W         900  W                                       Bias Voltage    100    V         120  V                                       Thickness       25     μm     0.03 μm                                   ______________________________________                                         • Conditions shown in Table 31                                     

                  TABLE 31                                                        ______________________________________                                                 Sample Name                                                          Raw Gas    2G    2H       2I  2J     2K  2L                                   ______________________________________                                        O.sub.2 (sccm)                                                                            0     3        5  8      9   10                                   NO (sccm)  20    14       10  4      2    0                                   ______________________________________                                    

                  TABLE 32                                                        ______________________________________                                                    Sample Name                                                       Evaluation Item                                                                             2G     2H     2I  2B   2J  2K   2L                              ______________________________________                                        Initial Properties                                                            Chargeability ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Sensitivity   ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Image Blurring                                                                              ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Residual Potential                                                                          ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Ghost         ◯                                                                        ◯                                                                        ◯                                                                     ◯                                                                      ◯                                                                     ◯                                                                      ◯                   Image Defect  ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Properties After                                                              Endurance in High-                                                            Humidity Environment                                                          Chargeability ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Sensitivity   ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Image Blurring                                                                              ◯                                                                        ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ◯                                                                      Δ                         Residual Potential                                                                          ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Ghost         ◯                                                                        ◯                                                                        ◯                                                                     ◯                                                                      ◯                                                                     ◯                                                                      ◯                   Image Defect  ◯                                                                        ◯                                                                        ◯                                                                     ◯                                                                      ◯                                                                     ◯                                                                      ◯                   Toner Filming X      Δ                                                                              ⊚                                                                  ⊚                                                                   ⊚                                                                  Δ                                                                            X                               ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 33                                                        ______________________________________                                        Component Ratio (Atomic %)                                                    Element 2G      2H     2I    2B   2J    2K   2L                               ______________________________________                                        Si (total)                                                                            11.7    12.1   11.7  11.7 11.5  11.0 10.7                             Si (Si--C)                                                                            8.5     8.9    9.0   8.7  8.8   8.2  8.7                              Si (Si--O)                                                                            5.3     4.5    3.2   2.7  1.4   0.8  0.6                              C (total)                                                                             23.8    23.9   25.1  23.8 26.1  27.1 26.8                             C (C--O)                                                                              5.2     5.3    5.3   5.2  5.1   5.7  5.0                              O (total)                                                                             5.7     5.5    5.6   5.7  5.3   4.9  5.7                              H       58.8    58.5   57.6  58.8 57.1  57.0 56.8                             ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  Si (Si--O) Component ratio of Si atoms having Si--O bonding.                  Si (C--O) Component ratio of C atoms having Ci--O bonding.               

EXAMPLE 15

Electrophotographic light-receiving members were formed by using theproduction apparatus shown in FIG. 6 according to the same procedure asthat used in Example 13. The conditions for forming a photoconductivelayer and a surface layer were as shown in Table 34. However, in orderto change the ratio of silicon atoms combined with oxygen atoms in thesurface layer, the flow rates of nitrogen monoxide gas and oxygen gaswere changed so that drums were respectively formed under the conditionsshown by the six samples 2M to 2R in Table 35. In addition, separatesurface layers were formed on the same cylinder as that used in Example13 by using the same apparatus as that shown in FIG. 6.

The thus-formed drums and sample were evaluated and analyzed by the samemethod as that employed in Example 13.

The results of evaluation and initial quantitative analytical values areshown in Tables 36 and 37. It was found from the results that there is aproper ratio of carbon atoms combined with oxygen atoms. Each of thedrums showed significant superiority in the properties after theendurance test in a high-humidity environment.

                  TABLE 34                                                        ______________________________________                                                      Layer Structure                                                                 Photo-                                                        Film-Forming    conductive       Surface                                      Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      35   sccm                                    Si (CH.sub.3).sub.4                                                                           0      sccm      70   sccm                                    CH.sub.4        0      sccm      •                                                                            sccm                                    (CH.sub.3).sub.2 O                                                                            0      sccm      •                                                                            sccm                                    O.sub.2         0      sccm      •                                                                            sccm                                    NO              3      sccm      •                                                                            sccm                                    B.sub.2 H.sub.6 50     ppm       0    ppm                                     H.sub.2         100    sccm      400  sccm                                    Pressure        8      mtorr     9    mtorr                                   Microwave Power 1000   W         900  W                                       Bias Voltage    100    V         120  V                                       Thickness       25     μm     0.03 μm                                   ______________________________________                                         • Conditions shown in Table 35                                     

                  TABLE 35                                                        ______________________________________                                                   Sample Name                                                        Raw gas      2M     2N       2O  2P    2Q  2R                                 ______________________________________                                        CH.sub.4 (sccm)                                                                            0      10       20  40    50  60                                 (CH.sub.3).sub.2 O (sccm)                                                                  40     33       26  14     7   0                                 O.sub.2 (sccm)                                                                             0       3        5   9    11  14                                 NO (sccm)    0       2        4   8    10  12                                 ______________________________________                                    

                  TABLE 36                                                        ______________________________________                                                    Sample Name                                                       Evaluation Item                                                                             2M     2N     2O  2B   2P  2Q   2R                              ______________________________________                                        Initial Properties                                                            Chargeability ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Sensitivity   ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Image Blurring                                                                              ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Residual Potential                                                                          ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Ghost         ◯                                                                        ◯                                                                        ◯                                                                     ◯                                                                      ◯                                                                     ◯                                                                      ◯                   Image Defect  ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Properties After                                                              Endurance in High-                                                            Humidity Environment                                                          Chargeability ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Sensitivity   ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Image Blurring                                                                              ◯                                                                        ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ◯                                                                      Δ                         Residual Potential                                                                          ⊚                                                                     ⊚                                                                     ⊚                                                                  ⊚                                                                   ⊚                                                                  ⊚                                                                   ⊚                Ghost         ◯                                                                        ◯                                                                        ◯                                                                     ◯                                                                      ◯                                                                     ◯                                                                      ◯                   Image Defect  ◯                                                                        ◯                                                                        ◯                                                                     ◯                                                                      ◯                                                                     ◯                                                                      ◯                   Toner Filming X      Δ                                                                              ⊚                                                                  ⊚                                                                   ⊚                                                                  Δ                                                                            X                               ______________________________________                                         ⊚ Very Good                                                    ◯ Good                                                            Δ No Practical Difficulty                                               X Not Practical Under the Circumstances                                  

                  TABLE 37                                                        ______________________________________                                        Component Ratio (Atomic %)                                                    Element 2M      2N     2O    2B   2P    2Q   2R                               ______________________________________                                        Si (total)                                                                            12.1    12.3   11.9  11.7 11.8  11.7 12.0                             Si (Si--C)                                                                            8.7     9.0    9.1   8.7  8.7   8.8  8.9                              Si (Si--O)                                                                            2.8     2.7    2.5   2.7  3.0   2.7  2.9                              C (total)                                                                             23.7    24.1   25.0  23.8 24.8  24.7 24.3                             C (C--O)                                                                              10.7    8.9    6.8   5.2  3.0   1.7  1.2                              O (total)                                                                             5.6     5.5    5.7   5.7  5.3   4.9  5.2                              H       58.6    58.1   57.4  58.8 58.1  58.7 58.5                             ______________________________________                                         Si (Si--C) Component ratio of Si atoms having Si--C bonding.                  Si (Si--O) Component ratio of Si atoms having Si--O bonding.                  Si (C--O) Component ratio of C atoms having C--O bonding.                

EXAMPLE 16

A charge injection inhibition layer, a photoconductive layer and a lowersurface layer were formed on a substrate by using the productionapparatus shown in FIG. 6 under the conditions shown in Table 38, and asurface layer was then formed thereon under the same conditions as thosein Sample 2A of Example 13.

As a result of evaluation of the thus-formed drum in the same way as inExample 13, good results were obtained, like the drum formed under theconditions for Sample 2A of Example 13.

                  TABLE 38                                                        ______________________________________                                                  Layer Structure                                                                 Charge                                                                        Injection  Photo-     Lower                                       Film-Forming                                                                              Inhibition conductive Surface                                     Condition   Layer      Layer      Layer                                       ______________________________________                                        Raw Gas                                                                       Flow Rate                                                                     SiH.sub.4   350    sccm    350  sccm  70   sccm                               He          100    sccm    100  sccm  100  sccm                               CH.sub.4    35     sccm    0    sccm  350  sccm                               B.sub.2 H.sub.6                                                                           1000   ppm     0    ppm   0    ppm                                Pressure    10     mtorr   9    mtorr 11   mtorr                              Microwave Power                                                                           1000   W       1000 W     1000 W                                  Bias Voltage                                                                              100    V       100  V     100  V                                  Thickness   3      μm   20   μm 0.5  μm                              ______________________________________                                    

EXAMPLE 17

A photoconductive layer was formed under the conditions shown in Table39, and a surface layer was then formed under the same conditions asthose for Sample 2B of Example 13.

As a result of evaluation of the thus-formed drum in the same way as inExample 13, good results were obtained, like the drum formed under theconditions for Sample 2B of Example 13.

                  TABLE 39                                                        ______________________________________                                                  Layer Structure                                                                 Charge                                                                        Injection  Charge     Charge                                      Film-Forming                                                                              Inhibition Transport  Injection                                   Condition   Layer      Layer      Layer                                       ______________________________________                                        Raw Gas                                                                       Flow Rate                                                                     SiH.sub.4   350    sccm    350  sccm  350  sccm                               He          100    sccm    100  sccm  100  sccm                               CH.sub.4    35     sccm    35   sccm  0    sccm                               B.sub.2 H.sub.6                                                                           1000   ppm     0    ppm   0    ppm                                Pressure    10     mtorr   10   mtorr 9    mtorr                              Microwave Power                                                                           1000   W       1000 W     1000 W                                  Bias Voltage                                                                              100    V       100  V     100  V                                  Thickness   3      μm   20   μm 5    μm                              ______________________________________                                    

EXAMPLE 18

A photoconductive layer was formed by the RF discharge process under theconditions shown in Table 40, and a surface layer was then formed byusing the production apparatus shown in FIG. 6 under the same conditionsas those for Sample 2B of Example 13.

As a result of evaluation of the thus-formed drum in the same way as inExample 13, good results were obtained, like the drum formed under theconditions for Sample 2B of Example 13.

                  TABLE 40                                                        ______________________________________                                                      Layer Structure                                                                 Charge                                                                        Injection        Photo-                                       Film-Forming    Inhibition       conductive                                   Condition       Layer            Layer                                        ______________________________________                                        Raw Gas Flow Rate                                                             SiH.sub.4       350    sccm      350  sccm                                    He              250    sccm      350  sccm                                    CH.sub.4        0      sccm      0    sccm                                    B.sub.2 H.sub.6 1000   ppm       0    ppm                                     Pressure        0.3    torr      0.5  torr                                    RF Power        300    W         400  W                                       Thickness       3      μm     25   μm                                   ______________________________________                                    

EXAMPLE 19

The same photoconductive layer as that formed in Example 13 was formed,and a surface layer was then formed under the same conditions as thosefor Sample 2B of Example 13, while the thickness was changed from 5Å to1 μm.

As a result of evaluation of the thus-formed drum in the same manner asin Example 13, good results were obtained from samples comprising thesurface layers having thicknesses from 10Å to 500Å, like the drum formedunder the conditions for Sample 2B of Example 13. The advantages of thepresent invention were thus confirmed.

EXAMPLE 20

The same evaluation as that performed in Examples 13 to 19 wasperformed, while the contents of silicon, carbon, oxygen and hydrogenatoms in the surface layer were changed. As a result, it was confirmedthat assuming that the composition of a surface layer is (Si_(x) C_(y)O_(z))_(t) Hu (wherein x+y+z=1, t+u=1), when 0.1 ≦x≦0.4, 0.4≦y≦0.7,0.05≦z≦0.2, 0.3≦t≦0.59 and 0.41≦u≦0.7, the drum of the present inventionshows good electrophotographic properties. The advantages of the presentinvention were thus confirmed.

The electrophotographic light-receiving member of the present inventionwhich is designed so as to have the above-described layer structure iscapable of solving all the problems and exhibits excellent electrical,optical and photoconductive properties and excellent durability andworking environmental properties.

The present invention can also provide an electrophotographiclight-receiving member excellent in preventing filming.

Particularly, the present invention enables the attainment of a greateffect of preventing filming of a toner for pressure fixing.

While the present invention has been described with respect to what ispresently considered to be the preferred embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments. To the contrary, the invention is intended to cover variousmodifications and equivalent formulations included within the spirit andscope of the appended claims. The scope of the following claims is to beaccorded the broadest interpretation so as to encompass all suchmodifications and equivalent formulations and functions.

What is claimed is:
 1. An electrophotographic light-receiving membercomprising a substrate and a light-receiving layer formed on saidsubstrate, said light-receiving layer has a surface layer or asurface-side region formed of a non-single crystal material comprisingsilicon, carbon and hydrogen atoms, wherein the ratio of silicon atomseach having at least one bond to a carbon atom in said surface layer orsurface-side region is at least 50% of the total number of silicon atomsin said surface layer or surface-side region.
 2. An electrophotographiclight-receiving member according to claim 1, wherein the content ofcarbon atoms in said surface layer or said surface-side region is 40 to90 atomic % of the total number of silicon and carbon atoms in saidsurface layer or surface-side region.
 3. An electrophotographiclight-receiving member according to claim 1, wherein the content ofhydrogen atoms in said surface layer or said surface-side region is 41to 70 atomic % of the total number of atoms in said surface layer orsurface-side region.
 4. An electrophotographic light-receiving memberaccording to claim 1, wherein said surface layer or surface-side regionfurther comprises oxygen atoms.
 5. An electrophotographiclight-receiving member according to claim 4, wherein the ratio ofsilicon atoms each having at least one bond to one of said oxygen atomsin said surface layer or surface-side region is 10 to 30 atomic % of thetotal number of silicon atoms in said surface layer or surface-sideregion.
 6. An electrophotographic light-receiving member according toclaim 1, wherein said surface layer or surface-side region furthercomprises oxygen atoms, the ratio of silicon atoms each having at leastone bond to one of said oxygen atoms is 10 to 30 atomic % of the totalnumber of silicon atoms in said surface layer or surface-side region,and the ratio of said carbon atoms each having at least one bond withone of said oxygen atoms is 10 to 30 atomic % of the total number ofcarbon atoms in said surface layer or surface-side region.
 7. Anelectrophotographic light-receiving member comprising a non-singlecrystal layer comprising at least silicon, carbon, oxygen and hydrogenatoms on an outermost surface layer, wherein the ratio of silicon atomscombined with carbon atoms in said non-single crystal layer is 50 to 100atomic % of the total number of silicon atoms therein, the ratio ofsilicon atoms combined with oxygen atoms in said non-single crystallayer is 10 to 30 atomic % of the total number of silicon atoms therein,and said non-single crystal layer is substantially composed of anon-single crystal (Si_(x) C_(y) O_(z))_(t) H_(u) wherein 0.1≦x≦0.4,0.4≦y≦0.7, 0.05≦ z≦0.2, x+y+z=1, 0.3≦t≦0.59, 0.41≦u≦0.7, and t+u=1. 8.An electrophotographic light-receiving member according to claim 7,wherein the thickness of said non-single crystal layer is 10 to 500 Å.9. An electrophotographic light-receiving member, comprising anon-single crystal layer comprising at least silicon, carbon, oxygen andhydrogen atoms on an outermost surface, wherein the ratio of siliconatoms combined with carbon atoms in said non-single crystal layer is 50to 100 atomic % of the total number of silicon atoms therein, the ratioof silicon atoms combined with oxygen atoms is 10 to 30 atomic % of thetotal number of silicon atoms therein, the ratio of carbon atomscombined with oxygen atoms is 10 to 30 atomic % of the total number ofcarbon atoms therein and said non-single crystal layer is substantiallycomposed of non-single crystal silicon having the formula (Si_(x) C_(y)O_(z))_(t) H_(u) wherein 0.1≦x≦0.4, 0.4≦y≦0.7, 0.05≦ z≦0.2, x+y+z=1 andt+u=1.
 10. An electrophotographic light-receiving member according toclaim 9, wherein 0.3≦t≦0.59 and 0.41≦ u≦0.7 in said formula (Si_(x)C_(y) O_(z))_(t) H_(u).
 11. An electrophotographic light-receivingmember according to claim 9, wherein the thickness of said non-singlecrystal layer is 10 to 500 Å.
 12. An electrophotographic light-receivingmember according to claim 1, wherein the ratio of silicon atoms eachhaving at least one bond to a carbon atoms in said surface layer orsurface-side region is at least 60% of the total number of silicon atomsin said surface layer or surface-side region.
 13. An electrophotographiclight-receiving member according to claim 12, wherein said ratio is atleast 70%.